fix(workflows): assert HEAD on per-agent branch before worktree commits (#2924) (#2941)

* fix(workflows): assert HEAD on per-agent branch before worktree commits

Worktree-mode setup could leave HEAD attached to a protected branch (master),
causing agent commits to land there. The previous response was a destructive
self-recovery via 'git update-ref refs/heads/master <sha>', which silently
rewinds the protected branch and destroys concurrent commits in multi-active
scenarios (parallel agents, user committing while agent runs).

- Reorder <worktree_branch_check> in execute-phase.md and quick.md to assert
  HEAD via 'git symbolic-ref' BEFORE any 'git reset --hard'. HALT with a
  blocker if HEAD is on main/master/develop/trunk/release/* or detached.
- Add a per-commit HEAD assertion (step 0) to gsd-executor.md
  <task_commit_protocol>; HEAD attachment can drift after 'git checkout <sha>'.
- Forbid 'git update-ref refs/heads/<protected>' in
  <destructive_git_prohibition>; surface the blocker rather than self-heal.
- Remove '--no-verify' as the worktree-mode default in execute-phase.md,
  execute-plan.md, quick.md, and references/git-integration.md. Hooks now
  run on every executor commit; opt out only via workflow.worktree_skip_hooks.
- Add regression test that parses the worktree_branch_check blocks structurally
  and asserts the symbolic-ref check precedes the reset --hard, no workflow
  performs update-ref on a protected ref, and --no-verify is no longer the
  default in any parallel-execution prompt.

* fix(#2924): address CodeRabbit review findings on worktree HEAD PR

- Add positive worktree-agent-* allow-list to <task_commit_protocol> step 0
  in gsd-executor.md and to <worktree_branch_check> in execute-phase.md and
  quick.md. The deny-list (main|master|develop|trunk|release/*) silently
  allowed feature/* and other arbitrary branches outside the agent namespace.
- Register workflow.worktree_skip_hooks in both config schemas
  (sdk/src/query/config-schema.ts and get-shit-done/bin/lib/config-schema.cjs)
  and document it in docs/CONFIGURATION.md so config-set accepts it.
- Fix stash lifecycle in execute-phase.md post-wave hook validation: stash
  under a named ref and pop after the hook run; warn on pop failure.
- Pre-dispatch PLAN.md commit in quick.md: gate on git diff --cached --quiet
  for idempotency and exit 1 with a clear error on commit failure (both the
  --no-verify and the normal branches) — no more swallowing real errors.
- Test fixes (tests/bug-2924-worktree-head-attachment.test.cjs):
  - Parse the protected-branch alternation structurally and require
    main, master, develop, trunk, release/.* (release/* was previously
    skipped by the \\b...\\b regex).
  - Use fs.readdirSync(dir, { recursive: true }) so workflows in nested
    subdirectories are also asserted against the update-ref ban.
  - Add allow-list assertions for execute-phase.md, quick.md, and
    gsd-executor.md to lock in the new positive namespace check.

* test(#2924): assert sub-section end marker exists before slicing

* test(#2924): use section boundary instead of fixed window for parallel-agents slice

docs/CONFIGURATION.md

@@ -191,6 +191,7 @@ All workflow toggles follow the **absent = enabled** pattern. If a key is missin
 | `workflow.skip_discuss` | boolean | `false` | When `true`, `/gsd-autonomous` bypasses the discuss-phase entirely, writing minimal CONTEXT.md from the ROADMAP phase goal. Useful for projects where developer preferences are fully captured in PROJECT.md/REQUIREMENTS.md. Added in v1.28 |
 | `workflow.text_mode` | boolean | `false` | Replaces AskUserQuestion TUI menus with plain-text numbered lists. Required for Claude Code remote sessions (`/rc` mode) where TUI menus don't render. Can also be set per-session with `--text` flag on discuss-phase. Added in v1.28 |
 | `workflow.use_worktrees` | boolean | `true` | When `false`, disables git worktree isolation for parallel execution. Users who prefer sequential execution or whose environment does not support worktrees can disable this. Added in v1.31 |
+| `workflow.worktree_skip_hooks` | boolean | `false` | When `true`, executor agents in worktree mode pass `--no-verify` (skipping pre-commit hooks) and post-wave hook validation runs against the merged result instead. Opt-in escape hatch for projects whose hooks cannot run in agent worktrees. Default `false` runs hooks on every commit (#2924). |
 | `workflow.code_review` | boolean | `true` | Enable `/gsd-code-review` and `/gsd-code-review-fix` commands. When `false`, the commands exit with a configuration gate message. Added in v1.34 |
 | `workflow.code_review_depth` | string | `standard` | Default review depth for `/gsd-code-review`: `quick` (pattern-matching only), `standard` (per-file analysis), or `deep` (cross-file with import graphs). Can be overridden per-run with `--depth=`. Added in v1.34 |
 | `workflow.plan_bounce` | boolean | `false` | Run external validation script against generated plans. When enabled, the plan-phase orchestrator pipes each PLAN.md through the script specified by `plan_bounce_script` and blocks on non-zero exit. Added in v1.36 |