fix(#2825): gsd-code-fixer honors workflow.use_worktrees; never rm -rf a reparse point (#2905)

* fix(#2825): gsd-code-fixer honors workflow.use_worktrees; never rm -rf a reparse point

gsd-code-fixer was the only writer that hand-rolled a git worktree inside the
agent prompt and the only one that never read workflow.use_worktrees. With the
setting explicitly false, --fix still created worktrees; the fresh worktree had
no node_modules, so runs improvised a teardown whose `rm -rf` followed a Windows
junction into the REAL node_modules (silent data loss, 3x observed).

Defect 1: gate setup_worktree + its cleanup tail on workflow.use_worktrees
(same gsd_run query config-get read the four sibling workflows use). When false:
edit/commit in the main checkout (wt='.', no temp branch, no sentinel, no cleanup).

Defect 2: forbid rm -rf on a possible reparse point in the spec — never fall
through to a destructive remove; on failure, stop and surface the error.

Defect 3: REVIEW-FIX records where verification ran (main checkout vs worktree).

The transactional worktree path (#2839/#2990/#2686) is unchanged when worktrees
are enabled. Docs-parity guards in tests/code-review.test.cjs bind the spec to
the fix.

* chore(#2825): backfill changeset PR 2905

* fix(#2825): drop stale agents/gsd-code-fixer.toml ack + spent entries (emitted-attribution)

gsd-test failed: agents/gsd-code-fixer.toml is a STALE ack here — that TOML was
changed by #2834 (now in next), not this PR. The 4 base-carried acks
(autonomous/discuss-phase-assumptions/next/plan-phase) are spent/inert.

---------

Co-authored-by: Test <test@example.com>

.changeset/quick-birds-run.md

@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 2905
+---
+**`/gsd-code-review --fix` now honors `workflow.use_worktrees`** — when the setting is `false`, the fixer edits and commits in the main checkout instead of creating a git worktree (matching the other writer workflows), and the spec forbids `rm -rf` on a possible Windows reparse point so an improvised worktree teardown can no longer delete the real `node_modules`. The REVIEW-FIX report also records where verification ran.