feat(onboard/parity): 写入汇 WriteSink 与写入前计划 plan_onboarding（P8c，待独立审查）

一键接入改写子项目受版本管理的文件，人在确认前必须看得到改什么；计划与 apply 走同一段
分发代码、只换写入汇，所以「看到的」就是「将写的」。

- lib.rs：WriteSink trait（read/write，内容忽略行尾未变不写）与 DiskSink
- 接入包模板分发、蓝图规则同步、项目身份与 MCP 投影（context、settings 兼容条目、
  liangjing、Codex 托管块）全部改经写入汇；原入口改为 DiskSink 薄包装，行为不变
- onboard/plan.rs：PlanSink 只记录不落盘、后续步骤读到前面步骤的待写内容；
  write_project_files 为 plan 与 apply 共用的写入序列；plan_onboarding 给出逐文件
  create/update/noop、有上限的 diff、混合文件预警（P10 前移到写入前）、身份冲突、
  手写条目与共享项目键阻断项，并对计划算 digest
- mcp_inject：plan_onboarding 生产入口与本机侧预计动作（token、稳定入口、三端只读
  状态、Codex 信任），只读、不起子进程
- 新增测试：空仓库全 create 且目录快照字节不变、apply 后两次计划全 noop 且 digest
  相同、CRLF 判 noop、内容/本机状态变化 digest 变化、混合文件与身份冲突阻断、
  手写 Codex 条目与共享键阻断、记录汇覆盖与撤销、diff 截断、Codex 信任解析；
  cargo test 307 passed

Feature-Confirmed: true
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src-tauri/src/commands/blueprint.rs

@@ -1270,33 +1270,55 @@ pub(crate) const BLUEPRINT_MANAGED_END: &str = "<!-- BLUEPRINT_MANAGED_END -->";
 /// 在指定文件中写入/替换 BLUEPRINT_MANAGED 块：
 /// 文件不存在 → 用 header + 模板创建；已有 MANAGED 区 → 原位替换（内容不变则不写）；否则追加。
 /// 返回动作：created | updated | unchanged | appended
+#[cfg(test)]
 fn upsert_managed_block(
     path: &Path,
     template: &str,
     header_when_created: &str,
+) -> Result<String, String> {
+    upsert_managed_block_with(path, template, header_when_created, &crate::DiskSink)
+}
+
+fn upsert_managed_block_with(
+    path: &Path,
+    template: &str,
+    header_when_created: &str,
+    sink: &dyn crate::WriteSink,
 ) -> Result<String, String> {
     let label = path.file_name().and_then(|n| n.to_str()).unwrap_or("file");
-    if !path.exists() {
+    let Some(content) = sink
+        .read(path)
+        .map_err(|e| format!("读取 {label} 失败: {e}"))?
+    else {
         let content = format!("{header_when_created}\n\n{template}\n");
-        std::fs::write(path, content).map_err(|e| format!("创建 {label} 失败: {e}"))?;
+        sink.write(path, &content)
+            .map_err(|e| format!("创建 {label} 失败: {e}"))?;
         return Ok("created".to_string());
-    }
+    };
-    let content = std::fs::read_to_string(path).map_err(|e| format!("读取 {label} 失败: {e}"))?;
     if content.contains(BLUEPRINT_MANAGED_START) {
         let new_content = replace_managed_section(&content, template);
-        let written = crate::write_if_content_changed(path, &new_content)
+        let written = sink
+            .write(path, &new_content)
             .map_err(|e| format!("更新 {label} 失败: {e}"))?;
         Ok(if written { "updated" } else { "unchanged" }.to_string())
     } else {
         let new_content = format!("{}\n\n{template}\n", content.trim_end());
-        std::fs::write(path, new_content).map_err(|e| format!("追加 {label} 失败: {e}"))?;
+        sink.write(path, &new_content)
+            .map_err(|e| format!("追加 {label} 失败: {e}"))?;
         Ok("appended".to_string())
     }
 }
 
 #[tauri::command]
 pub fn sync_blueprint_rules(project_path: String) -> Result<SyncResult, String> {
-    let root = Path::new(&project_path);
+    sync_blueprint_rules_with(Path::new(&project_path), &crate::DiskSink)
+}
+
+/// sync_blueprint_rules 的写入汇注入版：plan 用记录汇得到同一份结果而不落盘（P8c）。
+pub(crate) fn sync_blueprint_rules_with(
+    root: &Path,
+    sink: &dyn crate::WriteSink,
+) -> Result<SyncResult, String> {
     let bp_dir = root.join(".blueprint");
     let project_name = root
         .file_name()
@@ -1304,28 +1326,29 @@ pub fn sync_blueprint_rules(project_path: String) -> Result<SyncResult, String>
         .unwrap_or("Project")
         .to_string();
 
-    // 确保 .blueprint/ 存在
+    // 1. 写入 CONVENTIONS.md（使用当前生效版本：用户版优先，fallback 内置；内容不变则不写；
-    std::fs::create_dir_all(&bp_dir).map_err(|e| format!("创建 .blueprint/ 失败: {e}"))?;
+    //    .blueprint/ 由写入汇按需创建）
-
+    let conventions_written = sink
-    // 1. 写入 CONVENTIONS.md（使用当前生效版本：用户版优先，fallback 内置；内容不变则不写）
+        .write(
-    let conventions_written = crate::write_if_content_changed(
             &bp_dir.join("CONVENTIONS.md"),
             &effective_conventions_content(),
         )
         .map_err(|e| format!("写入 CONVENTIONS.md 失败: {e}"))?;
 
     // 2. AGENTS.md：完整蓝图工作流（跨工具单一来源，Qwen/Cursor/Copilot 均读）
-    let agents_action = upsert_managed_block(
+    let agents_action = upsert_managed_block_with(
         &root.join("AGENTS.md"),
         &agents_managed_template(),
         &format!("# AGENTS.md — {project_name}\n\n> 跨工具 AI 上下文入口（Claude / Qwen / Cursor / Copilot 等均读此文件）。"),
+        sink,
     )?;
 
     // 3. CLAUDE.md：薄引用（Claude 经 @AGENTS.md 接入单一来源）
-    let claude_action = upsert_managed_block(
+    let claude_action = upsert_managed_block_with(
         &root.join("CLAUDE.md"),
         &claude_managed_template(),
         &format!("# {project_name}"),
+        sink,
     )?;
 
     Ok(SyncResult {
@@ -3064,7 +3087,11 @@ mod tests {
         let before = std::fs::read(&f).unwrap();
         let a = upsert_managed_block(&f, tpl_v2, "# 头部").unwrap();
         assert_eq!(a, "unchanged");
-        assert_eq!(std::fs::read(&f).unwrap(), before, "CRLF 原样保留，未被 LF 重写");
+        assert_eq!(
+            std::fs::read(&f).unwrap(),
+            before,
+            "CRLF 原样保留，未被 LF 重写"
+        );
 
         // 3. 存在但无 MANAGED 区 → appended（既有内容保留）
         let g = dir.join("CLAUDE.md");

src-tauri/src/commands/onboarding.rs

@@ -55,17 +55,19 @@ impl TemplateResult {
 }
 
 /// 分发单个模板：存在则跳过（绝不覆盖），不存在则写入。
-fn dispatch_one(root: &Path, relative: &str, content: &str) -> TemplateResult {
+fn dispatch_one(
+    root: &Path,
+    relative: &str,
+    content: &str,
+    sink: &dyn crate::WriteSink,
+) -> TemplateResult {
     let target = root.join(relative);
-    if target.exists() {
+    match sink.read(&target) {
-        return TemplateResult::new(relative, "skipped", "已存在，未覆盖");
+        Ok(Some(_)) => return TemplateResult::new(relative, "skipped", "已存在，未覆盖"),
+        Ok(None) => {}
+        Err(e) => return TemplateResult::new(relative, "failed", format!("读取失败: {e}")),
     }
-    if let Some(parent) = target.parent() {
+    match sink.write(&target, content) {
-        if let Err(e) = std::fs::create_dir_all(parent) {
-            return TemplateResult::new(relative, "failed", format!("建目录失败: {e}"));
-        }
-    }
-    match std::fs::write(&target, content) {
         Ok(_) => TemplateResult::new(relative, "written", "已写入"),
         Err(e) => TemplateResult::new(relative, "failed", format!("写入失败: {e}")),
     }
@@ -73,20 +75,20 @@ fn dispatch_one(root: &Path, relative: &str, content: &str) -> TemplateResult {
 
 /// 全托管文件分发（三档升级语义之②，U1）：炼境独占管理、用户不定制（文件头有托管声明）。
 /// 不存在→written；与内嵌模板一致→skipped；不一致→覆盖 updated。
-/// 比较前归一化行尾（子项目 git autocrlf 可能把 LF 检出为 CRLF，避免永久 updated 抖动）。
+/// 比较忽略行尾（子项目 git autocrlf 可能把 LF 检出为 CRLF，避免永久 updated 抖动）。
-fn dispatch_fully_managed(root: &Path, relative: &str, content: &str) -> TemplateResult {
+fn dispatch_fully_managed(
+    root: &Path,
+    relative: &str,
+    content: &str,
+    sink: &dyn crate::WriteSink,
+) -> TemplateResult {
     let target = root.join(relative);
-    if !target.exists() {
+    if !matches!(sink.read(&target), Ok(Some(_))) {
-        return dispatch_one(root, relative, content);
+        return dispatch_one(root, relative, content, sink);
     }
-    let normalize = |s: &str| s.replace("\r\n", "\n");
+    match sink.write(&target, content) {
-    if let Ok(existing) = std::fs::read_to_string(&target) {
+        Ok(false) => TemplateResult::new(relative, "skipped", "内容已是最新模板"),
-        if normalize(&existing) == normalize(content) {
+        Ok(true) => TemplateResult::new(relative, "updated", "全托管文件已覆盖为最新模板"),
-            return TemplateResult::new(relative, "skipped", "内容已是最新模板");
-        }
-    }
-    match std::fs::write(&target, content) {
-        Ok(_) => TemplateResult::new(relative, "updated", "全托管文件已覆盖为最新模板"),
         Err(e) => TemplateResult::new(relative, "failed", format!("覆盖失败: {e}")),
     }
 }
@@ -107,7 +109,7 @@ fn node_pnpm_contract_present(root: &Path) -> bool {
         .unwrap_or(false)
 }
 
-fn dispatch_toolchain_resolver(root: &Path) -> TemplateResult {
+fn dispatch_toolchain_resolver(root: &Path, sink: &dyn crate::WriteSink) -> TemplateResult {
     if !node_pnpm_contract_present(root) {
         return TemplateResult::new(
             "mise.toml",
@@ -115,7 +117,7 @@ fn dispatch_toolchain_resolver(root: &Path) -> TemplateResult {
             "非 .nvmrc + pnpm packageManager 项目，不适用 Node/pnpm 工具链包",
         );
     }
-    dispatch_one(root, "mise.toml", TMPL_MISE)
+    dispatch_one(root, "mise.toml", TMPL_MISE, sink)
 }
 
 /// 从模板中提取 ONBOARDING_MANAGED 块（含首尾标记行）。
@@ -135,19 +137,22 @@ fn block_version(text: &str) -> Option<&str> {
 }
 
 /// 版本化分发（三态）：不存在→写全新；有标记→原位升级块；无标记→末尾追加块。
-fn dispatch_versioned(root: &Path, relative: &str, template: &str) -> TemplateResult {
+fn dispatch_versioned(
+    root: &Path,
+    relative: &str,
+    template: &str,
+    sink: &dyn crate::WriteSink,
+) -> TemplateResult {
     let target = root.join(relative);
     let tpl_block = match extract_managed_block(template) {
         Some(b) => b,
-        None => return dispatch_one(root, relative, template), // 模板无标记，退化为旧行为
+        None => return dispatch_one(root, relative, template, sink), // 模板无标记，退化为旧行为
     };
     let tpl_ver = block_version(tpl_block).unwrap_or("?");
 
-    if !target.exists() {
+    let content = match sink.read(&target) {
-        return dispatch_one(root, relative, template);
+        Ok(Some(c)) => c,
-    }
+        Ok(None) => return dispatch_one(root, relative, template, sink),
-    let content = match std::fs::read_to_string(&target) {
-        Ok(c) => c,
         Err(e) => return TemplateResult::new(relative, "failed", format!("读取失败: {e}")),
     };
 
@@ -174,7 +179,7 @@ fn dispatch_versioned(root: &Path, relative: &str, template: &str) -> TemplateRe
             )
         };
 
-    match std::fs::write(&target, new_content) {
+    match sink.write(&target, &new_content) {
         Ok(_) => TemplateResult::new(relative, action, detail),
         Err(e) => TemplateResult::new(relative, "failed", format!("写入失败: {e}")),
     }
@@ -184,33 +189,50 @@ fn dispatch_versioned(root: &Path, relative: &str, template: &str) -> TemplateRe
 /// project_path 为项目根（WSL 项目为 \\wsl.localhost\... UNC 路径，可直接写）。
 pub fn dispatch_templates(project_path: &str) -> Vec<TemplateResult> {
     let root = Path::new(project_path.trim_end_matches(['/', '\\']));
+    dispatch_templates_with(root, &crate::DiskSink)
+}
+
+/// dispatch_templates 的写入汇注入版：plan 用记录汇得到同一份结果而不落盘（P8c）。
+pub(crate) fn dispatch_templates_with(
+    root: &Path,
+    sink: &dyn crate::WriteSink,
+) -> Vec<TemplateResult> {
     vec![
-        dispatch_versioned(root, "AGENTS.md", TMPL_AGENTS),
+        dispatch_versioned(root, "AGENTS.md", TMPL_AGENTS, sink),
-        dispatch_one(root, "lefthook.yml", TMPL_LEFTHOOK),
+        dispatch_one(root, "lefthook.yml", TMPL_LEFTHOOK, sink),
-        dispatch_versioned(root, "docs/ai-context/git-workflow.md", TMPL_GIT_WORKFLOW),
+        dispatch_versioned(
-        dispatch_fully_managed(root, ".claude/commands/envoy.md", TMPL_ENVOY),
+            root,
+            "docs/ai-context/git-workflow.md",
+            TMPL_GIT_WORKFLOW,
+            sink,
+        ),
+        dispatch_fully_managed(root, ".claude/commands/envoy.md", TMPL_ENVOY, sink),
         dispatch_fully_managed(
             root,
             ".claude/hooks/blueprint-gate.cjs",
             TMPL_BLUEPRINT_GATE,
+            sink,
         ),
         dispatch_fully_managed(
             root,
             ".agents/skills/lian-jing/SKILL.md",
             TMPL_LIANJING_SKILL,
+            sink,
         ),
         // Claude Code 不读 .agents/skills，同一模板投影一份（单一来源，双投影）。
         dispatch_fully_managed(
             root,
             ".claude/skills/lian-jing/SKILL.md",
             TMPL_LIANJING_SKILL,
+            sink,
         ),
         dispatch_fully_managed(
             root,
             ".lian-jing/capability-packs.json",
             TMPL_CAPABILITY_PACKS,
+            sink,
         ),
-        dispatch_toolchain_resolver(root),
+        dispatch_toolchain_resolver(root, sink),
     ]
 }
 
@@ -222,7 +244,7 @@ pub fn dispatch_templates(project_path: &str) -> Vec<TemplateResult> {
 
 /// 接入包会原位改写托管块的文件：AGENTS.md、git-workflow.md 由模板分发写 ONBOARDING_MANAGED，
 /// AGENTS.md、CLAUDE.md 另由 buff 的蓝图规则同步写 BLUEPRINT_MANAGED。
-const MANAGED_BLOCK_FILES: [&str; 3] =
+pub(crate) const MANAGED_BLOCK_FILES: [&str; 3] =
     ["AGENTS.md", "docs/ai-context/git-workflow.md", "CLAUDE.md"];
 
 /// 比较块外内容时整体剔除的托管块（开始标记前缀，结束标记）。
@@ -266,7 +288,7 @@ fn outside_managed_differs(head: Option<&str>, worktree: &str) -> bool {
 
 /// 目标文件在 git 中是否有托管块之外的未提交改动（未跟踪文件带块外内容也算）。
 /// 非 git 仓库、git 不可用或命令失败一律返回 false：只做提示，探测失败不打扰调用方。
-fn has_uncommitted_outside_managed(root: &Path, relative: &str, worktree: &str) -> bool {
+pub(crate) fn has_uncommitted_outside_managed(root: &Path, relative: &str, worktree: &str) -> bool {
     // --no-optional-locks：后台探测不抢 index.lock，避免与 agent 同时进行的提交冲突
     let status = crate::silent_cmd("git")
         .args([
@@ -298,7 +320,7 @@ fn has_uncommitted_outside_managed(root: &Path, relative: &str, worktree: &str)
     outside_managed_differs(head.as_deref(), worktree)
 }
 
-fn mixed_file_warning(relative: &str) -> String {
+pub(crate) fn mixed_file_warning(relative: &str) -> String {
     format!(
         "{relative}：块外有未提交改动，升级后将成为混合文件——本次只改写了其中的炼境托管块，块外内容未动；\
          提交前先确认块外改动的归属（不得用字符串手术拆分暂存），无法整体提交时交人定案。"
@@ -2242,19 +2264,19 @@ mod tests {
         std::fs::create_dir_all(&base).unwrap();
 
         // 不存在 → written
-        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容");
+        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容", &crate::DiskSink);
         assert_eq!(r.action, "written");
 
         // 一致 → skipped（CRLF 检出也视为一致）
-        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容");
+        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容", &crate::DiskSink);
         assert_eq!(r.action, "skipped");
         std::fs::write(base.join("envoy.md"), "v2 内容".replace('\n', "\r\n")).unwrap();
-        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容");
+        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容", &crate::DiskSink);
         assert_eq!(r.action, "skipped", "仅行尾差异不应触发覆盖");
 
         // 不一致（旧版模板/被改动）→ 覆盖 updated
         std::fs::write(base.join("envoy.md"), "v1 旧内容").unwrap();
-        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容");
+        let r = dispatch_fully_managed(&base, "envoy.md", "v2 内容", &crate::DiskSink);
         assert_eq!(r.action, "updated");
         assert_eq!(
             std::fs::read_to_string(base.join("envoy.md")).unwrap(),
@@ -2305,7 +2327,7 @@ mod tests {
         )
         .unwrap();
 
-        let first = dispatch_toolchain_resolver(&base);
+        let first = dispatch_toolchain_resolver(&base, &crate::DiskSink);
         assert_eq!(first.action, "written");
         assert_eq!(check_toolchain_resolver(&base).state, VerifyState::Ready);
 
@@ -2314,7 +2336,7 @@ mod tests {
             "[tasks.custom]\nrun = 'project-owned'\n",
         )
         .unwrap();
-        let second = dispatch_toolchain_resolver(&base);
+        let second = dispatch_toolchain_resolver(&base, &crate::DiskSink);
         assert_eq!(second.action, "skipped");
         assert_eq!(
             std::fs::read_to_string(base.join("mise.toml")).unwrap(),

src-tauri/src/lib.rs

@@ -41,6 +41,41 @@ pub(crate) fn write_if_content_changed(
     std::fs::write(path, content).map(|()| true)
 }
 
+/// 接入写入汇（agent-client-parity P8c）：接入包、蓝图规则、项目身份与 MCP 投影这些项目文件写入
+/// 只经它读写。`DiskSink` 真实写入；onboard::plan 的记录汇只记录不落盘，并让后续步骤读到前面
+/// 步骤的待写内容（同一文件被两步先后改写时，计划与实际写入算出同样的结果）。
+pub(crate) trait WriteSink {
+    /// 读取当前内容（含本汇里尚未落盘的待写内容）；文件不存在返回 Ok(None)。
+    fn read(&self, path: &std::path::Path) -> std::io::Result<Option<String>>;
+    /// 内容（忽略行尾）未变返回 Ok(false)；否则写入（必要时先建父目录）并返回 Ok(true)。
+    fn write(&self, path: &std::path::Path, content: &str) -> std::io::Result<bool>;
+}
+
+/// 真实写入：内容不变不重写（write_if_content_changed），父目录按需创建。
+pub(crate) struct DiskSink;
+
+impl WriteSink for DiskSink {
+    fn read(&self, path: &std::path::Path) -> std::io::Result<Option<String>> {
+        match std::fs::read_to_string(path) {
+            Ok(text) => Ok(Some(text)),
+            Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(None),
+            Err(error) => Err(error),
+        }
+    }
+
+    fn write(&self, path: &std::path::Path, content: &str) -> std::io::Result<bool> {
+        if let Some(existing) = self.read(path)? {
+            if same_text_ignoring_eol(&existing, content) {
+                return Ok(false);
+            }
+        }
+        if let Some(parent) = path.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+        std::fs::write(path, content).map(|()| true)
+    }
+}
+
 /// 创建不弹 CMD 窗口的子进程（Windows 专用 CREATE_NO_WINDOW 标志）。
 /// 所有后台静默命令都应通过此函数创建，避免在 Windows 上频繁闪出黑框。
 pub(crate) fn silent_cmd(program: &str) -> std::process::Command {

src-tauri/src/mcp_inject.rs

@@ -168,20 +168,22 @@ fn settings_path(project_id: &str) -> Result<PathBuf, String> {
         .join("settings.json"))
 }
 
-fn liangjing_path(project_id: &str) -> Result<PathBuf, String> {
-    Ok(project_root(project_id)?
-        .join(".claude")
-        .join("liangjing.json"))
-}
-
 fn codex_config_path(project_id: &str) -> Result<PathBuf, String> {
     Ok(project_root(project_id)?.join(".codex").join("config.toml"))
 }
 
 fn read_context_object(path: &PathBuf, label: &str) -> Result<Value, String> {
-    match std::fs::read_to_string(path) {
+    read_context_object_with(path, label, &crate::DiskSink)
-        Ok(content) if content.trim().is_empty() => Ok(json!({})),
+}
-        Ok(content) => serde_json::from_str::<Value>(&content)
+
+fn read_context_object_with(
+    path: &std::path::Path,
+    label: &str,
+    sink: &dyn crate::WriteSink,
+) -> Result<Value, String> {
+    match sink.read(path) {
+        Ok(Some(content)) if content.trim().is_empty() => Ok(json!({})),
+        Ok(Some(content)) => serde_json::from_str::<Value>(&content)
             .map_err(|error| format!("读取 {label} 失败（{}）: {error}", path.display()))
             .and_then(|value| {
                 if value.is_object() {
@@ -193,59 +195,135 @@ fn read_context_object(path: &PathBuf, label: &str) -> Result<Value, String> {
                     ))
                 }
             }),
-        Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(json!({})),
+        Ok(None) => Ok(json!({})),
         Err(error) => Err(format!("读取 {label} 失败（{}）: {error}", path.display())),
     }
 }
 
-/// 现有 JSON 文件与待写值语义相同（与键序、缩进、行尾、末尾换行无关）时不重写：
+/// 现有 JSON 文本与待写值语义相同（与键序、缩进、行尾、末尾换行无关）时不重写：
 /// Claude Code 等客户端改写这些文件时用自己的键序与格式，按文本比较会让炼境每次注入都整文件重排。
-fn json_file_equals(path: &std::path::Path, value: &Value) -> bool {
+fn json_text_equals(existing: Option<&str>, value: &Value) -> bool {
-    std::fs::read_to_string(path)
+    existing
-        .ok()
         .and_then(|text| serde_json::from_str::<Value>(text.trim_start_matches('\u{feff}')).ok())
         .is_some_and(|existing| &existing == value)
 }
 
-fn write_context_object(path: &PathBuf, value: &Value, label: &str) -> Result<(), String> {
+/// 语义相同不写；否则以 pretty JSON 经写入汇写入（父目录由写入汇按需创建）。
-    if json_file_equals(path, value) {
+fn write_json_with(
+    path: &std::path::Path,
+    value: &Value,
+    label: &str,
+    sink: &dyn crate::WriteSink,
+) -> Result<(), String> {
+    let existing = sink
+        .read(path)
+        .map_err(|error| format!("读取 {label} 失败: {error}"))?;
+    if json_text_equals(existing.as_deref(), value) {
         return Ok(());
     }
-    if let Some(parent) = path.parent() {
-        std::fs::create_dir_all(parent)
-            .map_err(|error| format!("创建 {label} 目录失败: {error}"))?;
-    }
     let content = serde_json::to_string_pretty(value).map_err(|error| error.to_string())?;
-    crate::write_if_content_changed(path, &content)
+    sink.write(path, &content)
         .map(|_| ())
         .map_err(|error| format!("写入 {label} 失败: {error}"))
 }
 
 /// 写工具无关的项目身份锚点。项目根目录是边界，客户端项目 UI 或用户级配置均不是身份来源。
 /// 合并写入：保留未来字段与项目定制字段，只有炼境拥有的身份字段会被刷新。
+#[cfg(test)]
 fn write_canonical_context_at(root: &std::path::Path, project_id: &str) -> Result<(), String> {
+    write_canonical_context_with(root, project_id, &crate::DiskSink)
+}
+
+pub(crate) fn write_canonical_context_with(
+    root: &std::path::Path,
+    project_id: &str,
+    sink: &dyn crate::WriteSink,
+) -> Result<(), String> {
     let path = root.join(".lian-jing").join("context.json");
-    let mut ctx = read_context_object(&path, "canonical 项目上下文")?;
+    let mut ctx = read_context_object_with(&path, "canonical 项目上下文", sink)?;
     let obj = ctx.as_object_mut().expect("ctx 必为 JSON 对象");
     obj.insert("schema_version".into(), json!(CONTEXT_SCHEMA_VERSION));
     obj.insert("project_id".into(), json!(project_id));
-    write_context_object(&path, &ctx, "canonical 项目上下文")
+    write_json_with(&path, &ctx, "canonical 项目上下文", sink)
-}
-
-fn write_canonical_context(project_id: &str) -> Result<(), String> {
-    let root = project_root(project_id)?;
-    write_canonical_context_at(&root, project_id)
 }
 
 /// 写旧 Claude 上下文投影。它不是项目身份的单一事实来源，保留是为了兼容已接入项目。
-fn write_liangjing_context(project_id: &str, port: u16) -> Result<(), String> {
+pub(crate) fn write_liangjing_context_with(
-    let path = liangjing_path(project_id)?;
+    root: &std::path::Path,
-    let mut ctx = read_context_object(&path, "Claude 兼容上下文")?;
+    project_id: &str,
+    port: u16,
+    sink: &dyn crate::WriteSink,
+) -> Result<(), String> {
+    let path = root.join(".claude").join("liangjing.json");
+    let mut ctx = read_context_object_with(&path, "Claude 兼容上下文", sink)?;
     let obj = ctx.as_object_mut().expect("ctx 必为 JSON 对象");
     obj.insert("project_id".into(), json!(project_id));
     obj.insert("mcp_port".into(), json!(port));
     obj.remove("group_id");
-    write_context_object(&path, &ctx, "Claude 兼容上下文")
+    write_json_with(&path, &ctx, "Claude 兼容上下文", sink)
+}
+
+/// 项目 .claude/settings.json 的兼容条目（Claude Code 不读其 mcpServers，仅保留作兼容）：
+/// 无人值守默认值只在缺省时写入，清理旧组级 key，写入单一 lian-jing 条目。
+pub(crate) fn write_settings_compat_with(
+    root: &std::path::Path,
+    server_url: &str,
+    sink: &dyn crate::WriteSink,
+) -> Result<(), String> {
+    let path = root.join(".claude").join("settings.json");
+    let mut settings = match sink.read(&path) {
+        Ok(None) => json!({}),
+        Ok(Some(content)) if content.trim().is_empty() => json!({}),
+        Ok(Some(content)) => serde_json::from_str(&content).map_err(|e| {
+            format!(
+                "settings.json 格式错误，请手动修复后重试（{}）: {}",
+                path.display(),
+                e
+            )
+        })?,
+        Err(e) => return Err(format!("读取 settings.json 失败: {}", e)),
+    };
+
+    let obj = settings
+        .as_object_mut()
+        .ok_or("settings.json 顶层必须是 JSON 对象")?;
+
+    // 炼境管理的项目需要无人值守运行（/ship 等技能不应被 permission 弹窗打断）
+    obj.entry("permissions")
+        .or_insert(json!({"defaultMode": "bypassPermissions"}));
+
+    let servers = obj.entry("mcpServers").or_insert(json!({}));
+
+    if let Some(map) = servers.as_object_mut() {
+        map.retain(|k, _| !k.starts_with(LEGACY_KEY_PREFIX));
+    }
+    servers[MCP_KEY] = json!({
+        "type": "sse",
+        "url": server_url
+    });
+    write_json_with(&path, &settings, "settings.json", sink)
+}
+
+/// 项目侧 MCP 文件（canonical context、Claude 兼容投影、Codex 托管块）一次写齐；
+/// inject 与 onboard::plan 共用同一序列，计划与实际写入的结果一致。返回 Codex 托管块结果。
+pub(crate) fn write_project_mcp_files_with(
+    root: &std::path::Path,
+    project_id: &str,
+    port: u16,
+    server_url: &str,
+    header_helper: &str,
+    sink: &dyn crate::WriteSink,
+) -> Result<ClientOutcome, String> {
+    write_canonical_context_with(root, project_id, sink)?;
+    write_settings_compat_with(root, server_url, sink)?;
+    write_liangjing_context_with(root, project_id, port, sink)?;
+    Ok(upsert_codex_mcp_config_with(
+        &root.join(".codex").join("config.toml"),
+        server_url,
+        header_helper,
+        sink,
+    )
+    .unwrap_or_else(|reason| ClientOutcome::Failed { reason }))
 }
 
 /// 查找 claude CLI 路径（优先环境变量 CLAUDE_BIN，然后常用安装目录，最后 where 命令）
@@ -1347,16 +1425,7 @@ fn read_json(path: &PathBuf) -> Result<Value, String> {
 }
 
 fn write_json(path: &PathBuf, value: &Value) -> Result<(), String> {
-    if json_file_equals(path, value) {
+    write_json_with(path, value, "settings.json", &crate::DiskSink)
-        return Ok(());
-    }
-    if let Some(parent) = path.parent() {
-        std::fs::create_dir_all(parent).map_err(|e| format!("创建 .claude 目录失败: {}", e))?;
-    }
-    let content = serde_json::to_string_pretty(value).map_err(|e| e.to_string())?;
-    crate::write_if_content_changed(path, &content)
-        .map(|_| ())
-        .map_err(|e| format!("写入 settings.json 失败: {}", e))
 }
 
 fn render_codex_block(server_url: &str, header_helper: &str) -> Result<String, String> {
@@ -1417,13 +1486,21 @@ fn upsert_codex_mcp_config(
     path: &PathBuf,
     server_url: &str,
     header_helper: &str,
+) -> Result<ClientOutcome, String> {
+    upsert_codex_mcp_config_with(path, server_url, header_helper, &crate::DiskSink)
+}
+
+fn upsert_codex_mcp_config_with(
+    path: &std::path::Path,
+    server_url: &str,
+    header_helper: &str,
+    sink: &dyn crate::WriteSink,
 ) -> Result<ClientOutcome, String> {
     let block = render_codex_block(server_url, header_helper)?;
-    let current = match std::fs::read_to_string(path) {
+    let current = sink
-        Ok(value) => value,
+        .read(path)
-        Err(error) if error.kind() == std::io::ErrorKind::NotFound => String::new(),
+        .map_err(|error| format!("读取 Codex config.toml 失败: {error}"))?
-        Err(error) => return Err(format!("读取 Codex config.toml 失败: {error}")),
+        .unwrap_or_default();
-    };
     let (start, end) = (
         current.find(CODEX_MCP_MANAGED_START),
         current.find(CODEX_MCP_MANAGED_END),
@@ -1448,11 +1525,7 @@ fn upsert_codex_mcp_config(
         (None, None) => format!("{}\n{}", current.trim_end(), block),
     };
 
-    if let Some(parent) = path.parent() {
+    sink.write(path, &next)
-        std::fs::create_dir_all(parent)
-            .map_err(|error| format!("创建 .codex 目录失败: {error}"))?;
-    }
-    crate::write_if_content_changed(path, &next)
         .map(|written| {
             if written {
                 ClientOutcome::Applied
@@ -1538,34 +1611,12 @@ fn inject_project_mcp_locked(
     )?;
     ensure_header_shim()?;
     let header_helper = shim_helper_command(&digest);
-    write_canonical_context(project_id)?;
-    let path = settings_path(project_id)?;
-    let mut settings = read_json(&path)?;
-
-    let obj = settings
-        .as_object_mut()
-        .ok_or("settings.json 顶层必须是 JSON 对象")?;
-
-    // 炼境管理的项目需要无人值守运行（/ship 等技能不应被 permission 弹窗打断）
-    obj.entry("permissions")
-        .or_insert(json!({"defaultMode": "bypassPermissions"}));
-
-    let servers = obj.entry("mcpServers").or_insert(json!({}));
-
-    if let Some(map) = servers.as_object_mut() {
-        map.retain(|k, _| !k.starts_with(LEGACY_KEY_PREFIX));
-    }
-    servers[MCP_KEY] = json!({
-        "type": "sse",
-        "url": server_url
-    });
-
-    write_json(&path, &settings)?;
-
-    // 保留 Claude 历史上下文作为兼容投影；项目身份以 .lian-jing/context.json 为准。
-    write_liangjing_context(project_id, port)?;
-
     let root = project_root(project_id)?;
+    write_canonical_context_with(&root, project_id, &crate::DiskSink)?;
+    write_settings_compat_with(&root, &server_url, &crate::DiskSink)?;
+    // 保留 Claude 历史上下文作为兼容投影；项目身份以 .lian-jing/context.json 为准。
+    write_liangjing_context_with(&root, project_id, port, &crate::DiskSink)?;
+
     let facts = project_facts(project_id, &root);
     let desired = DesiredMcp {
         port,
@@ -1636,6 +1687,166 @@ pub fn client_static_status(project_id: &str) -> Vec<ClientReport> {
         .collect()
 }
 
+// ── 一键接入计划（P8c）：本机侧预计动作 + 项目文件演算 ──────────────────────────
+
+/// 一键接入写入前计划（只读：不写文件、不起子进程）。P8e 接入 MCP / Tauri 投影前暂无生产调用方。
+#[allow(dead_code)]
+pub(crate) fn plan_onboarding(
+    project_id: &str,
+) -> Result<crate::onboard::plan::OnboardingPlan, String> {
+    let root = project_root(project_id)?;
+    let port = crate::mcp_server::read_port();
+    let digest = crate::credential_store::mcp_auth_digest(project_id)?;
+    let server_url = crate::mcp_server::scoped_mcp_url(port, project_id);
+    let header_helper = shim_helper_command(&digest);
+    let project = crate::onboard::plan::ProjectWrite {
+        project_id,
+        port,
+        server_url: &server_url,
+        header_helper: &header_helper,
+    };
+    Ok(crate::onboard::plan::plan_onboarding(
+        &root,
+        &project,
+        plan_machine_steps(project_id, &root),
+    ))
+}
+
+/// 本机侧（不进仓库）的预计动作：项目 token、稳定 helper 入口、三端客户端配置（只读判定）、Codex 信任。
+#[allow(dead_code)]
+fn plan_machine_steps(
+    project_id: &str,
+    root: &std::path::Path,
+) -> Vec<crate::onboard::plan::MachineStep> {
+    use crate::onboard::plan::MachineStep;
+    let step = |step: &str, status: &str, detail: String| MachineStep {
+        step: step.into(),
+        status: status.into(),
+        detail,
+    };
+    let mut steps = vec![
+        if is_project_injected(&crate::credential_store::WindowsCredentialStore, project_id) {
+            step(
+                "token",
+                "noop",
+                "项目 MCP 认证 token 已在本机受保护存储".into(),
+            )
+        } else {
+            step(
+                "token",
+                "apply",
+                "将在本机受保护存储生成项目 MCP 认证 token".into(),
+            )
+        },
+        shim_step(),
+    ];
+    for report in client_static_status(project_id) {
+        let name = match report.client {
+            ClientId::Claude => "claude",
+            ClientId::Codex => "codex",
+            ClientId::Dsh => "dsh",
+        };
+        steps.push(step(
+            name,
+            outcome_status(&report.outcome),
+            report.outcome.describe(),
+        ));
+    }
+    steps.push(match codex_trusts(root) {
+        Some(true) => step("codex_trust", "noop", "Codex 已信任该目录".into()),
+        Some(false) => step(
+            "codex_trust",
+            "needs_human",
+            "Codex 只在目录受信任后才加载项目 .codex/config.toml：请在 Codex 里信任该目录（炼境不改 Codex 信任表）".into(),
+        ),
+        None => step("codex_trust", "not_installed", "未发现 Codex 配置".into()),
+    });
+    steps
+}
+
+#[allow(dead_code)]
+fn shim_step() -> crate::onboard::plan::MachineStep {
+    let (status, detail) = match (helper_bin_dir(), std::env::current_exe()) {
+        (Ok(dir), Ok(exe)) => {
+            let path = dir.join(MCP_HEADER_SHIM_NAME);
+            let expected = render_header_shim(&exe);
+            if std::fs::read_to_string(&path).ok().as_deref() == Some(expected.as_str()) {
+                ("noop", format!("稳定入口已是最新：{}", path.display()))
+            } else {
+                ("apply", format!("将写入稳定入口：{}", path.display()))
+            }
+        }
+        (Err(error), _) => ("unavailable", error),
+        (_, Err(_)) => ("unavailable", "无法定位炼境可执行文件".into()),
+    };
+    crate::onboard::plan::MachineStep {
+        step: "shim".into(),
+        status: status.into(),
+        detail,
+    }
+}
+
+/// 只读判定结果 → 计划里的本机动作状态。
+#[allow(dead_code)]
+fn outcome_status(outcome: &ClientOutcome) -> &'static str {
+    match outcome {
+        ClientOutcome::Converged => "noop",
+        ClientOutcome::Missing
+        | ClientOutcome::Applied
+        | ClientOutcome::Refreshed
+        | ClientOutcome::Removed
+        | ClientOutcome::Deferred => "apply",
+        ClientOutcome::NotInstalled => "not_installed",
+        ClientOutcome::NotApplicable { .. } => "not_applicable",
+        ClientOutcome::ManualKept => "manual_kept",
+        ClientOutcome::OtherProject { .. } => "other_project",
+        ClientOutcome::NeedsHuman { .. } => "needs_human",
+        ClientOutcome::Unavailable { .. } | ClientOutcome::Failed { .. } => "unavailable",
+    }
+}
+
+/// Codex 用户配置里是否把该目录（或其祖先目录）标为 trusted；未发现 Codex 配置返回 None。
+/// 只读、只认 `[projects.'<路径>']` 段下的 `trust_level = "trusted"`（P4-0 H-P8-1：未信任目录不加载项目配置）。
+#[allow(dead_code)]
+fn codex_trusts(root: &std::path::Path) -> Option<bool> {
+    let home = std::env::var_os("CODEX_HOME")
+        .map(PathBuf::from)
+        .or_else(|| {
+            std::env::var_os("USERPROFILE").map(|home| PathBuf::from(home).join(".codex"))
+        })?;
+    let text = std::fs::read_to_string(home.join("config.toml")).ok()?;
+    Some(codex_config_trusts(&text, &root.display().to_string()))
+}
+
+#[allow(dead_code)]
+fn codex_config_trusts(config: &str, root: &str) -> bool {
+    let normalize = |path: &str| {
+        path.replace('/', "\\")
+            .trim_end_matches('\\')
+            .to_lowercase()
+    };
+    let root = normalize(root);
+    let mut section: Option<String> = None;
+    for line in config.lines().map(str::trim) {
+        if line.starts_with('[') {
+            section = line
+                .strip_prefix("[projects.")
+                .and_then(|rest| rest.strip_suffix(']'))
+                .map(|key| normalize(key.trim_matches(['\'', '"'])));
+            continue;
+        }
+        let Some(key) = &section else { continue };
+        let covers = &root == key || root.starts_with(&format!("{key}\\"));
+        let trusted = line.split_once('=').is_some_and(|(name, value)| {
+            name.trim() == "trust_level" && value.trim().trim_matches('"') == "trusted"
+        });
+        if covers && trusted {
+            return true;
+        }
+    }
+    false
+}
+
 // ── 三端客户端适配器（注册表见 onboard::clients::registry）──────────────────────
 
 pub(crate) struct ClaudeAdapter;
@@ -2092,7 +2303,7 @@ mod tests {
         std::fs::write(&path, client_written).unwrap();
         let value: Value = serde_json::from_str(client_written).unwrap();
         write_json(&path, &value).unwrap();
-        write_context_object(&path, &value, "settings.json").unwrap();
+        write_json_with(&path, &value, "settings.json", &crate::DiskSink).unwrap();
         assert_eq!(
             std::fs::read_to_string(&path).unwrap(),
             client_written,
@@ -2656,6 +2867,29 @@ mod tests {
         ));
     }
 
+    #[test]
+    fn codex_trust_reads_projects_table_including_ancestors() {
+        let config = "model = \"x\"\n\n[projects.'e:\\code-project\\enterprise-system']\ntrust_level = \"trusted\"\n\n[projects.\"D:\\Work\"]\ntrust_level = \"trusted\"\n\n[projects.'e:\\other']\ntrust_level = \"untrusted\"\n";
+        assert!(codex_config_trusts(
+            config,
+            "E:\\code-project\\enterprise-system"
+        ));
+        assert!(codex_config_trusts(
+            config,
+            "E:/code-project/enterprise-system/"
+        ));
+        assert!(
+            codex_config_trusts(config, "d:\\work\\sub\\proj"),
+            "祖先目录受信任"
+        );
+        assert!(!codex_config_trusts(config, "E:\\other"), "untrusted 不算");
+        assert!(
+            !codex_config_trusts(config, "E:\\code-project\\enterprise-system-wt"),
+            "前缀不是路径边界"
+        );
+        assert!(!codex_config_trusts(config, "C:\\new"));
+    }
+
     #[test]
     fn hard_failure_is_only_codex_failed() {
         let report = |client, outcome| ClientReport::new(client, outcome);

src-tauri/src/onboard/mod.rs

@@ -6,6 +6,7 @@
 //! 存量入口（mcp_inject 等）按绞杀者模式逐步改成薄包装，不往这里扩散旧写法。
 
 pub mod clients;
+pub mod plan;
 
 #[cfg(test)]
 mod fitness_tests {

src-tauri/src/onboard/plan.rs

@@ -0,0 +1,588 @@
+//! 写入前计划（agent-client-parity P8c）：用记录汇把一键接入会写的项目文件「演算」一遍，
+//! 给出逐文件动作、有上限的 diff、混合文件预警与身份冲突，并对计划内容算 digest。
+//!
+//! 为什么：一键接入改写的是子项目受版本管理的文件，人在确认前必须看得到改什么；
+//! apply 时带上确认过的 digest，计划被改（文件变了、本机状态变了）就拒绝写入。
+//! 计划与 apply 走同一段分发代码（只换写入汇），所以「看到的」就是「将写的」。
+
+use crate::WriteSink;
+use serde::{Deserialize, Serialize};
+use std::cell::RefCell;
+use std::collections::BTreeMap;
+use std::path::{Path, PathBuf};
+
+/// 记录汇：只记录不落盘；读取优先返回本汇里的待写内容。
+#[derive(Default)]
+pub(crate) struct PlanSink {
+    pending: RefCell<BTreeMap<PathBuf, String>>,
+    touched: RefCell<Vec<PathBuf>>,
+}
+
+impl WriteSink for PlanSink {
+    fn read(&self, path: &Path) -> std::io::Result<Option<String>> {
+        if let Some(content) = self.pending.borrow().get(path) {
+            return Ok(Some(content.clone()));
+        }
+        read_disk(path)
+    }
+
+    fn write(&self, path: &Path, content: &str) -> std::io::Result<bool> {
+        {
+            let mut touched = self.touched.borrow_mut();
+            if !touched.iter().any(|seen| seen == path) {
+                touched.push(path.to_path_buf());
+            }
+        }
+        if let Some(current) = self.read(path)? {
+            if crate::same_text_ignoring_eol(&current, content) {
+                return Ok(false);
+            }
+        }
+        // 写回与磁盘一致（先改后又改回）时撤销待写，避免把「无变化」报成 update
+        let unchanged_on_disk =
+            read_disk(path)?.is_some_and(|disk| crate::same_text_ignoring_eol(&disk, content));
+        let mut pending = self.pending.borrow_mut();
+        if unchanged_on_disk {
+            pending.remove(path);
+        } else {
+            pending.insert(path.to_path_buf(), content.to_string());
+        }
+        Ok(true)
+    }
+}
+
+fn read_disk(path: &Path) -> std::io::Result<Option<String>> {
+    match std::fs::read_to_string(path) {
+        Ok(text) => Ok(Some(text)),
+        Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(None),
+        Err(error) => Err(error),
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum FileAction {
+    Create,
+    Update,
+    Noop,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct PlannedFile {
+    /// 相对项目根，统一用 /
+    pub path: String,
+    pub action: FileAction,
+    /// update 时的行级差异（有上限，超出截断并标注）；create 时为新文件概要
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub diff: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub warning: Option<String>,
+    /// 计划写入内容的 sha256（noop 为当前内容的 sha256），进入 digest
+    pub content_sha256: String,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum BlockReason {
+    /// 托管块文件块外有未提交改动，本次又要改写托管块
+    MixedFile,
+    /// .lian-jing/context.json 已属于别的 project_id
+    IdentityConflict,
+    /// 客户端已有手写同名配置（炼境不覆盖）
+    ManualEntry,
+    /// 生效的客户端条目属于别的项目（共享项目键）
+    SharedKey,
+    /// 需要人工处理或无法确认（读失败、标记错序等）
+    NeedsHuman,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct BlockedItem {
+    pub target: String,
+    pub reason: BlockReason,
+    pub detail: String,
+}
+
+/// 本机侧（不进仓库）的预计动作：token、稳定入口、三端客户端配置、Codex 信任等。
+/// status：noop（已就绪）| apply（apply 时会写）| not_installed | not_applicable | needs_human | unavailable。
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct MachineStep {
+    pub step: String,
+    pub status: String,
+    pub detail: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct OnboardingPlan {
+    pub project_id: String,
+    pub files: Vec<PlannedFile>,
+    pub machine_changes: Vec<MachineStep>,
+    pub blocked: Vec<BlockedItem>,
+    /// 覆盖项目文件新内容哈希、本机动作与阻断项；apply 须带回同一 digest
+    pub digest: String,
+}
+
+/// 接入要写的项目侧连接参数（与 inject 同源）。
+pub struct ProjectWrite<'a> {
+    pub project_id: &'a str,
+    pub port: u16,
+    pub server_url: &'a str,
+    pub header_helper: &'a str,
+}
+
+/// 一键接入的项目文件写入序列（接入包模板 → 蓝图规则 → 项目身份与 MCP 投影），plan 与 apply 共用。
+/// 返回分发过程中的失败与需人工项（不中断其余写入）。
+pub(crate) fn write_project_files(
+    root: &Path,
+    project: &ProjectWrite,
+    sink: &dyn WriteSink,
+) -> Vec<BlockedItem> {
+    let mut issues = Vec::new();
+    for result in crate::commands::onboarding::dispatch_templates_with(root, sink) {
+        if result.action == "failed" {
+            issues.push(BlockedItem {
+                target: result.name,
+                reason: BlockReason::NeedsHuman,
+                detail: result.detail,
+            });
+        }
+    }
+    if let Err(error) = crate::commands::blueprint::sync_blueprint_rules_with(root, sink) {
+        issues.push(BlockedItem {
+            target: ".blueprint/CONVENTIONS.md".into(),
+            reason: BlockReason::NeedsHuman,
+            detail: error,
+        });
+    }
+    use super::clients::ClientOutcome;
+    match crate::mcp_inject::write_project_mcp_files_with(
+        root,
+        project.project_id,
+        project.port,
+        project.server_url,
+        project.header_helper,
+        sink,
+    ) {
+        Ok(ClientOutcome::ManualKept) => issues.push(BlockedItem {
+            target: ".codex/config.toml".into(),
+            reason: BlockReason::ManualEntry,
+            detail: "已手工定义 [mcp_servers.lian-jing]，炼境不会覆盖".into(),
+        }),
+        Ok(ClientOutcome::Failed { reason }) | Err(reason) => issues.push(BlockedItem {
+            target: ".lian-jing/context.json 等项目 MCP 文件".into(),
+            reason: BlockReason::NeedsHuman,
+            detail: reason,
+        }),
+        Ok(_) => {}
+    }
+    issues
+}
+
+/// 只读：演算一键接入会对项目文件做的改动，叠加调用方给出的本机预计动作，生成计划与 digest。
+/// 不写任何文件（目录快照前后字节一致）。
+pub(crate) fn plan_onboarding(
+    root: &Path,
+    project: &ProjectWrite,
+    machine_changes: Vec<MachineStep>,
+) -> OnboardingPlan {
+    let sink = PlanSink::default();
+    let mut blocked = identity_conflict(root, project.project_id)
+        .into_iter()
+        .collect::<Vec<_>>();
+    blocked.extend(write_project_files(root, project, &sink));
+
+    let pending = sink.pending.borrow();
+    let mut files = Vec::new();
+    for path in sink.touched.borrow().iter() {
+        let relative = relative_path(root, path);
+        let disk = read_disk(path).ok().flatten();
+        let (action, content, diff) = match (pending.get(path), &disk) {
+            (Some(new), None) => (
+                FileAction::Create,
+                new.clone(),
+                Some(format!("新建，{} 行", new.lines().count())),
+            ),
+            (Some(new), Some(old)) => (
+                FileAction::Update,
+                new.clone(),
+                Some(bounded_diff(old, new, DIFF_LINE_LIMIT)),
+            ),
+            (None, current) => (FileAction::Noop, current.clone().unwrap_or_default(), None),
+        };
+        let mut warning = None;
+        if action == FileAction::Update
+            && crate::commands::onboarding::MANAGED_BLOCK_FILES.contains(&relative.as_str())
+            && crate::commands::onboarding::has_uncommitted_outside_managed(
+                root,
+                &relative,
+                disk.as_deref().unwrap_or(""),
+            )
+        {
+            let text = crate::commands::onboarding::mixed_file_warning(&relative);
+            blocked.push(BlockedItem {
+                target: relative.clone(),
+                reason: BlockReason::MixedFile,
+                detail: text.clone(),
+            });
+            warning = Some(text);
+        }
+        files.push(PlannedFile {
+            path: relative,
+            action,
+            diff,
+            warning,
+            content_sha256: sha256_hex(&content.replace("\r\n", "\n")),
+        });
+    }
+    for step in &machine_changes {
+        if let Some(reason) = match step.status.as_str() {
+            "manual_kept" => Some(BlockReason::ManualEntry),
+            "other_project" => Some(BlockReason::SharedKey),
+            "needs_human" => Some(BlockReason::NeedsHuman),
+            _ => None,
+        } {
+            blocked.push(BlockedItem {
+                target: step.step.clone(),
+                reason,
+                detail: step.detail.clone(),
+            });
+        }
+    }
+    let digest = plan_digest(project.project_id, &files, &machine_changes, &blocked);
+    OnboardingPlan {
+        project_id: project.project_id.to_string(),
+        files,
+        machine_changes,
+        blocked,
+        digest,
+    }
+}
+
+/// context.json 已有不同的 project_id：一键接入会改写身份锚点，必须人确认（不自动覆盖）。
+fn identity_conflict(root: &Path, project_id: &str) -> Option<BlockedItem> {
+    let text = read_disk(&root.join(".lian-jing").join("context.json")).ok()??;
+    let existing = serde_json::from_str::<serde_json::Value>(text.trim_start_matches('\u{feff}'))
+        .ok()?
+        .get("project_id")?
+        .as_str()?
+        .to_string();
+    (existing != project_id).then(|| BlockedItem {
+        target: ".lian-jing/context.json".into(),
+        reason: BlockReason::IdentityConflict,
+        detail: format!("目录已属于项目 {existing}，与本次接入的 {project_id} 不一致"),
+    })
+}
+
+fn relative_path(root: &Path, path: &Path) -> String {
+    path.strip_prefix(root)
+        .unwrap_or(path)
+        .to_string_lossy()
+        .replace('\\', "/")
+}
+
+fn sha256_hex(text: &str) -> String {
+    use sha2::Digest;
+    sha2::Sha256::digest(text.as_bytes())
+        .iter()
+        .map(|byte| format!("{byte:02x}"))
+        .collect()
+}
+
+/// digest 覆盖项目 ID、逐文件（路径、动作、内容哈希）、本机动作与阻断项。
+fn plan_digest(
+    project_id: &str,
+    files: &[PlannedFile],
+    machine: &[MachineStep],
+    blocked: &[BlockedItem],
+) -> String {
+    let canonical = serde_json::json!({
+        "project_id": project_id,
+        "files": files.iter().map(|f| (f.path.as_str(), f.action, f.content_sha256.as_str())).collect::<Vec<_>>(),
+        "machine": machine.iter().map(|m| (m.step.as_str(), m.status.as_str())).collect::<Vec<_>>(),
+        "blocked": blocked.iter().map(|b| (b.target.as_str(), b.reason)).collect::<Vec<_>>(),
+    });
+    sha256_hex(&canonical.to_string())
+}
+
+const DIFF_LINE_LIMIT: usize = 60;
+
+/// 行级差异（去掉公共前后缀后列出删除与新增行），超过 limit 行截断并注明总行数。
+fn bounded_diff(old: &str, new: &str, limit: usize) -> String {
+    let old = old.replace("\r\n", "\n");
+    let new = new.replace("\r\n", "\n");
+    let a: Vec<&str> = old.lines().collect();
+    let b: Vec<&str> = new.lines().collect();
+    let prefix = a.iter().zip(&b).take_while(|(x, y)| x == y).count();
+    let max_suffix = a.len().min(b.len()) - prefix;
+    let suffix = a
+        .iter()
+        .rev()
+        .zip(b.iter().rev())
+        .take(max_suffix)
+        .take_while(|(x, y)| x == y)
+        .count();
+    let mut lines = vec![format!("@@ 第 {} 行起", prefix + 1)];
+    lines.extend(
+        a[prefix..a.len() - suffix]
+            .iter()
+            .map(|line| format!("-{line}")),
+    );
+    lines.extend(
+        b[prefix..b.len() - suffix]
+            .iter()
+            .map(|line| format!("+{line}")),
+    );
+    let total = lines.len();
+    if total > limit {
+        lines.truncate(limit);
+        lines.push(format!("…（diff 共 {total} 行，只显示前 {limit} 行）"));
+    }
+    lines.join("\n")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn git(dir: &Path, args: &[&str]) {
+        let out = std::process::Command::new("git")
+            .args([
+                "-c",
+                "user.name=t",
+                "-c",
+                "user.email=t@t",
+                "-c",
+                "commit.gpgsign=false",
+                "-c",
+                "core.autocrlf=false",
+            ])
+            .args(args)
+            .current_dir(dir)
+            .output()
+            .expect("git 可执行");
+        assert!(
+            out.status.success(),
+            "git {args:?}: {}",
+            String::from_utf8_lossy(&out.stderr)
+        );
+    }
+
+    /// 目录快照：相对路径 → 字节（含 .git，证明 plan 零写入）。
+    fn snapshot(root: &Path) -> BTreeMap<String, Vec<u8>> {
+        let mut out = BTreeMap::new();
+        let mut pending = vec![root.to_path_buf()];
+        while let Some(dir) = pending.pop() {
+            for entry in std::fs::read_dir(&dir).unwrap() {
+                let path = entry.unwrap().path();
+                if path.is_dir() {
+                    pending.push(path);
+                } else {
+                    out.insert(relative_path(root, &path), std::fs::read(&path).unwrap());
+                }
+            }
+        }
+        out
+    }
+
+    const PROJECT: ProjectWrite<'static> = ProjectWrite {
+        project_id: "p8c-test",
+        port: 27190,
+        server_url: "http://127.0.0.1:27190/mcp/projects/p8c-test",
+        header_helper: "\"C:\\x\\lianjing-mcp-header.cmd\" abc",
+    };
+
+    fn machine(status: &str) -> Vec<MachineStep> {
+        vec![MachineStep {
+            step: "claude".into(),
+            status: status.into(),
+            detail: String::new(),
+        }]
+    }
+
+    fn temp_repo(name: &str) -> PathBuf {
+        let root = std::env::temp_dir().join(format!("lj_p8c_{name}_{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&root);
+        std::fs::create_dir_all(&root).unwrap();
+        git(&root, &["init", "-q"]);
+        std::fs::write(root.join("README.md"), "readme\n").unwrap();
+        git(&root, &["add", "-A"]);
+        git(&root, &["commit", "-q", "--no-verify", "-m", "init"]);
+        root
+    }
+
+    #[test]
+    fn plan_on_empty_repo_creates_everything_and_writes_nothing() {
+        let root = temp_repo("empty");
+        let before = snapshot(&root);
+        let plan = plan_onboarding(&root, &PROJECT, machine("apply"));
+        assert_eq!(snapshot(&root), before, "plan 不得写任何文件");
+        assert!(plan.files.len() >= 12, "实际 {} 个文件", plan.files.len());
+        assert!(
+            plan.files.iter().all(|f| f.action == FileAction::Create),
+            "{:?}",
+            plan.files
+        );
+        for expected in [
+            "AGENTS.md",
+            "CLAUDE.md",
+            ".blueprint/CONVENTIONS.md",
+            ".lian-jing/context.json",
+            ".claude/settings.json",
+            ".claude/liangjing.json",
+            ".codex/config.toml",
+            ".agents/skills/lian-jing/SKILL.md",
+            ".claude/skills/lian-jing/SKILL.md",
+        ] {
+            assert!(
+                plan.files.iter().any(|f| f.path == expected),
+                "缺 {expected}"
+            );
+        }
+        assert!(plan.blocked.is_empty(), "{:?}", plan.blocked);
+        assert_eq!(plan.digest.len(), 64);
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    #[test]
+    fn plan_after_apply_is_noop_and_digest_tracks_changes() {
+        let root = temp_repo("applied");
+        // apply：同一写入序列换成真实写入汇
+        assert!(write_project_files(&root, &PROJECT, &crate::DiskSink).is_empty());
+        git(&root, &["add", "-A"]);
+        git(&root, &["commit", "-q", "--no-verify", "-m", "onboard"]);
+
+        let first = plan_onboarding(&root, &PROJECT, machine("noop"));
+        let second = plan_onboarding(&root, &PROJECT, machine("noop"));
+        assert!(
+            first.files.iter().all(|f| f.action == FileAction::Noop),
+            "{:?}",
+            first.files
+        );
+        assert_eq!(first.digest, second.digest, "同一状态两次计划 digest 相同");
+
+        // 本机预计动作变化 → digest 变化
+        assert_ne!(
+            plan_onboarding(&root, &PROJECT, machine("apply")).digest,
+            first.digest
+        );
+
+        // CRLF 检出的同内容文件仍是 noop
+        let packs = root.join(".lian-jing/capability-packs.json");
+        // 模板在 Windows 检出时可能已是 CRLF：先归一成 LF 再整体转 CRLF，避免造出 \r\r\n
+        let lf = std::fs::read_to_string(&packs)
+            .unwrap()
+            .replace("\r\n", "\n");
+        std::fs::write(&packs, lf.replace('\n', "\r\n")).unwrap();
+        let crlf = plan_onboarding(&root, &PROJECT, machine("noop"));
+        let not_noop: Vec<_> = crlf
+            .files
+            .iter()
+            .filter(|f| f.action != FileAction::Noop)
+            .map(|f| (f.path.clone(), f.action, f.diff.clone()))
+            .collect();
+        assert!(not_noop.is_empty(), "{not_noop:?}");
+
+        // 任一目标文件内容变化 → 该文件 update、digest 变化
+        std::fs::write(&packs, "{}\n").unwrap();
+        let changed = plan_onboarding(&root, &PROJECT, machine("noop"));
+        let entry = changed
+            .files
+            .iter()
+            .find(|f| f.path == ".lian-jing/capability-packs.json")
+            .unwrap();
+        assert_eq!(entry.action, FileAction::Update);
+        assert!(entry.diff.as_deref().unwrap().contains("-{}"));
+        assert_ne!(changed.digest, first.digest);
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    #[test]
+    fn mixed_file_and_identity_conflict_are_blocked() {
+        let root = temp_repo("blocked");
+        assert!(write_project_files(&root, &PROJECT, &crate::DiskSink).is_empty());
+        // 把 AGENTS.md 的接入包托管块版本改旧并提交，让计划要升级它
+        let agents = root.join("AGENTS.md");
+        let text = std::fs::read_to_string(&agents).unwrap();
+        let start = text.find("ONBOARDING_MANAGED_START version=\"").unwrap()
+            + "ONBOARDING_MANAGED_START version=\"".len();
+        let end = start + text[start..].find('"').unwrap();
+        std::fs::write(&agents, format!("{}0.0.1{}", &text[..start], &text[end..])).unwrap();
+        git(&root, &["add", "-A"]);
+        git(&root, &["commit", "-q", "--no-verify", "-m", "old block"]);
+        // 块外未提交改动
+        let dirty = std::fs::read_to_string(&agents).unwrap() + "\n项目自己的未提交段落\n";
+        std::fs::write(&agents, dirty).unwrap();
+        // 身份锚点属于别的项目
+        std::fs::write(
+            root.join(".lian-jing/context.json"),
+            r#"{"schema_version":1,"project_id":"someone-else"}"#,
+        )
+        .unwrap();
+
+        let plan = plan_onboarding(&root, &PROJECT, machine("noop"));
+        let agents_entry = plan.files.iter().find(|f| f.path == "AGENTS.md").unwrap();
+        assert_eq!(agents_entry.action, FileAction::Update);
+        assert!(agents_entry.warning.is_some(), "混合文件须带预警");
+        assert!(plan
+            .blocked
+            .iter()
+            .any(|b| b.reason == BlockReason::MixedFile && b.target == "AGENTS.md"));
+        assert!(plan.blocked.iter().any(
+            |b| b.reason == BlockReason::IdentityConflict && b.detail.contains("someone-else")
+        ));
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    #[test]
+    fn manual_codex_entry_and_machine_manual_states_block() {
+        let root = temp_repo("manual");
+        std::fs::create_dir_all(root.join(".codex")).unwrap();
+        std::fs::write(
+            root.join(".codex/config.toml"),
+            "[mcp_servers.lian-jing]\nurl = \"http://manual/mcp\"\n",
+        )
+        .unwrap();
+        let plan = plan_onboarding(&root, &PROJECT, machine("other_project"));
+        assert!(plan
+            .blocked
+            .iter()
+            .any(|b| b.reason == BlockReason::ManualEntry && b.target == ".codex/config.toml"));
+        assert!(plan
+            .blocked
+            .iter()
+            .any(|b| b.reason == BlockReason::SharedKey && b.target == "claude"));
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    #[test]
+    fn plan_sink_overlays_pending_writes_and_reverts_to_noop() {
+        let root = std::env::temp_dir().join(format!("lj_p8c_sink_{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&root);
+        std::fs::create_dir_all(&root).unwrap();
+        let file = root.join("a.md");
+        std::fs::write(&file, "v1\n").unwrap();
+        let sink = PlanSink::default();
+        assert!(sink.write(&file, "v2\n").unwrap());
+        assert_eq!(
+            sink.read(&file).unwrap().as_deref(),
+            Some("v2\n"),
+            "后续步骤读到待写内容"
+        );
+        assert_eq!(std::fs::read_to_string(&file).unwrap(), "v1\n", "磁盘未动");
+        assert!(sink.write(&file, "v1\n").unwrap(), "改回磁盘原样");
+        assert!(sink.pending.borrow().is_empty(), "改回原样即撤销待写");
+        assert!(!sink.write(&file, "v1\r\n").unwrap(), "仅行尾不同视为未变");
+        let _ = std::fs::remove_dir_all(&root);
+    }
+
+    #[test]
+    fn bounded_diff_trims_common_lines_and_truncates() {
+        let diff = bounded_diff("a\nb\nc\n", "a\nB\nc\n", 60);
+        assert_eq!(diff, "@@ 第 2 行起\n-b\n+B");
+        let old: String = (0..200).map(|i| format!("o{i}\n")).collect();
+        let new: String = (0..200).map(|i| format!("n{i}\n")).collect();
+        let long = bounded_diff(&old, &new, 60);
+        assert_eq!(long.lines().count(), 61);
+        assert!(long.ends_with("…（diff 共 401 行，只显示前 60 行）"));
+    }
+}