🐛 fix(vscode): 实施启动改为复用已有 feature 分支

vscode/src/panel/handlers/sessions.ts

@@ -16,7 +16,7 @@ import { resolveProfilePath } from '../../cc/profiles'
 import { getBrainstormContinuePrompt, getImplementPlanPrompt } from '../../cc/prompts'
 import { projectsDirFor, watchForNewSession } from '../../cc/sessionWatcher'
 import { detectRepo } from '../../git/remote'
-import { createWorktree, resolveWorktreePath } from '../../git/worktree'
+import { ensureWorktree, resolveWorktreePath } from '../../git/worktree'
 import { updateIssueAssignees } from '../../gitea/api'
 import { logger } from '../../logging/logger'
 import { getSettings } from '../../settings/store'
@@ -766,45 +766,7 @@ export async function handleImplement(
   // 留空时回退到默认 ~/Sources/worktree/<项目>/<slug>。
   const worktreeTemplate = getSettings(panel.context).worktreeDirectory
     || '~/Sources/worktree/$project_name/$feature_name'
-  const worktreePath = resolveWorktreeDir(worktreeTemplate, workspaceRoot, slug)
-
-  // Pre-flight: refuse if either the directory or the branch already
-  // exists, since `git worktree add -b` would fail and we'd have to
-  // unwind partial state.
-  let worktreeExists = false
-  try {
-    await fsp.stat(worktreePath)
-    worktreeExists = true
-  }
-  catch {
-    // ENOENT — good.
-  }
-  let branchExists = false
-  try {
-    branchExists = await new Promise<boolean>((resolve) => {
-      execFile(
-        'git',
-        ['-C', workspaceRoot, 'branch', '--list', branch],
-        { timeout: 10_000 },
-        (err, stdout) => {
-          if (err) {
-            resolve(false)
-            return
-          }
-          resolve((stdout ?? '').trim().length > 0)
-        },
-      )
-    })
-  }
-  catch {
-    branchExists = false
-  }
-  if (worktreeExists || branchExists) {
-    void window.showErrorMessage(
-      `feature ${slug} 的 worktree 或分支已存在，请先清理`,
-    )
-    return
-  }
+  let worktreePath = resolveWorktreeDir(worktreeTemplate, workspaceRoot, slug)
 
   // 工单级 profilePath > 默认 fallback。工单的 profile 锁定可在工单详情面板里覆盖。
   const effectiveProfilePath = panel.resolveImplementProfilePath(profilePath)
@@ -834,20 +796,19 @@ export async function handleImplement(
     return
   }
 
-  // Create the worktree before anything else, so a worktree-add failure
-  // doesn't leave half-written state behind.
+  // 先保证 worktree 可用：后面写 state / 开终端都依赖实际 path。
   try {
     // worktree 现在建在工作区外（~/Sources/worktree/<项目>/...），父目录可能不存在；
     // git worktree add 不会创建多层父目录，先补齐。
     await fsp.mkdir(path.dirname(worktreePath), { recursive: true })
-    await createWorktree({ workspaceRoot, worktreePath, branch })
+    worktreePath = await ensureWorktree({ workspaceRoot, worktreePath, branch })
   }
   catch (err) {
     const message = err instanceof Error ? err.message : String(err)
     logger.add({
       level: 'error',
       source: 'implement',
-      message: 'git worktree add 失败',
+      message: 'ensureWorktree 失败',
       details: message,
     })
     void window.showErrorMessage(message)