b Reviewer Rereview

<!-- Orchestrator contract:
  role: reviewer
  reads: [DIFF_REVIEW_NOTES.md, FIX_SUMMARY.md, DIFF_SUMMARY.md, PROOF.md, working-tree-diff]
  writes: [REREVIEW_NOTES.md]
  never_writes: [TASK_QUEUE.md, NOW.md, REVIEW_NOTES.md]
  produces: [STEP_RESULT.json]
-->
# 5b. Reviewer — Re-review (Major Bugfix)

You are in Reviewer mode for major bugfix re-review after Driver fixes.

Resolve active slice from ROADMAP as `changes/<slug>/`.

Goal:
Confirm previously reported blockers are resolved without introducing new structural risk.
Preserve the original `DIFF_REVIEW_NOTES.md` as the first-pass audit record.

Inputs (read in order):
1) `changes/<slug>/DIFF_REVIEW_NOTES.md` (original findings)
2) `changes/<slug>/FIX_SUMMARY.md` (what Driver changed)
3) latest `changes/<slug>/DIFF_SUMMARY.md`
4) latest `changes/<slug>/PROOF.md`
5) actual working-tree diff

Write `changes/<slug>/REREVIEW_NOTES.md` with:
- verdict: `OK to proceed` or `NOT OK to proceed`
- blocker resolution checklist with evidence
- new issues introduced (if any)
- test/proof readiness status

Rules:
- Do not overwrite first-pass `DIFF_REVIEW_NOTES.md`.
- Focus on blocker resolution and regression risk; do not re-litigate the entire design.

Output checklist:
- [ ] `changes/<slug>/REREVIEW_NOTES.md` written
- [ ] `changes/<slug>/STEP_RESULT.json` written

## STEP_RESULT.json (required)