♻️ refactor(vscode): 抽出 worktreePath 模块（slug / 目录模板解析）

Claude-Session: https://claude.ai/code/session_011cEyL6k351U2BzX1Qmygph

vscode/src/git/worktreePath.ts

@@ -0,0 +1,42 @@
+import { createHash } from 'node:crypto'
+import * as os from 'node:os'
+import * as path from 'node:path'
+
+export const DEFAULT_WORKTREE_TEMPLATE = '~/Sources/worktree/$project_name/$feature_name'
+
+/**
+ * spec/plan 以目录形式存放（docs/superpowers/{specs,plans}/<slug>/…），slug 取
+ * `plans`/`specs` 后一段。兜底父目录名，再兜底路径 hash，保证目录名不为空。
+ */
+export function deriveSlug(planFile: string): string {
+  const segments = planFile.split('/').filter(Boolean)
+  const anchor = segments.findIndex(s => s === 'plans' || s === 'specs')
+  if (anchor >= 0 && segments[anchor + 1])
+    return segments[anchor + 1]
+  const parent = path.basename(path.dirname(planFile))
+  if (parent && parent !== '.' && parent !== '/')
+    return parent
+  return createHash('sha256').update(planFile).digest('hex').slice(0, 8)
+}
+
+/** 实施分支固定形如 `feature/<slug>`；接管方只有分支名，从这里反推 worktree 目录名。 */
+export function slugFromBranch(branch: string): string {
+  return branch.startsWith('feature/') ? branch.slice('feature/'.length) : branch
+}
+
+/**
+ * 把 worktreeDirectory 模板展开成绝对路径。`~` 在这里展开：git/execFile 不经 shell，
+ * 不会自己做 tilde 展开。
+ */
+export function resolveWorktreeDir(template: string, workspaceRoot: string, slug: string): string {
+  let p = template
+    .split('$project_name')
+    .join(path.basename(workspaceRoot))
+    .split('$project_root')
+    .join(workspaceRoot)
+    .split('$feature_name')
+    .join(slug)
+  if (p.startsWith('~'))
+    p = path.join(os.homedir(), p.slice(1))
+  return path.resolve(p)
+}