feat(review-workflow): raise A-bar with capability, sweep, live-state, and role-boundary proofs (#179)

Extends review_proofs.py with the four #179 proofs, the successor set to
the #173 checkout/inventory proofs:

- assess_capability_evidence: a capability claim (review_pr, merge_pr, ...)
  counts only with exact evidence citing gitea_resolve_task_capability
  output or equivalent runtime context; no claims at all fails closed.
- assess_sweep_evidence: secret/provenance sweeps must state the exact
  command/script/pattern/named method, the scope scanned, and a boolean
  result; vague summaries are downgraded and a missing sweep fails closed.
- assess_live_state_recheck: an explicit pre-mutation recheck must prove
  the PR is still open, the live head equals the pinned head (full
  40-hex), the base branch is unchanged, and blocking review state was
  checked and absent; not performing it fails closed.
- assess_role_boundary: a reviewer run using an author namespace (or vice
  versa) is clean only with an explicit justification; unreported
  namespace usage fails closed.

build_final_report now takes the four proofs as keyword arguments: any
missing or failed proof downgrades the grade, merge_allowed additionally
requires the proven live-state recheck, and a merge performed without it
is a blocked violation. Existing #173 semantics are unchanged otherwise;
gates only get stricter.

tests/test_review_proofs.py adds 29 tests covering the issue's harness
assertions: capability claims without evidence downgraded, vague sweeps
downgraded, missing/stale live-state recheck downgrades and blocks merge
(violation when a merge is claimed anyway), unjustified author-namespace
use downgraded, and the #173 positive baseline preserved.

SKILL.md sections F/G and the review-pr/merge-pr templates now require the
capability evidence, exact sweep, pre-verdict and pre-merge live-state
rechecks, and reviewer-namespace discipline.

Closes #179

Co-Authored-By: Claude Fable 5 <[email protected]>

skills/llm-project-workflow/templates/merge-pr.md

@@ -20,10 +20,21 @@ Steps:
    *If the current identity does not match the required role (or is the PR author), STOP. Relaunch/switch to the correct profile first.*
 2. Verify authenticated identity + active profile.
 3. Confirm PR #<pr>: author (not you), state open, mergeable, review approved. Check if PR body uses `Closes #N` or `Fixes #N`; if it uses `Implements #N` or `Refs #N`, manual closing will be needed in step 29.
-4. If any gate fails → STOP and report.
-4. Merge with explicit confirmation (e.g. confirmation="MERGE PR <pr>"),
-   optionally pinning the reviewed head SHA / changed-file set.
-5. Confirm remote master now contains the merge commit (or the expected changes if squash merged).
+4. Capability evidence (#179): cite the exact gitea_resolve_task_capability
+   output (or runtime context) proving merge_pr is allowed — a bare
+   "capability checks passed" claim is downgraded.
+5. Final live-state recheck (#179), immediately before the merge mutation —
+   re-read the live PR and prove:
+   - PR still open
+   - live head SHA still equals the pinned/reviewed head SHA
+   - base branch unchanged
+   - no undismissed REQUEST_CHANGES / blocking review state remains
+   If any recheck fails → STOP, re-pin, re-validate.
+6. If any gate fails → STOP and report.
+7. Merge with explicit confirmation (e.g. confirmation="MERGE PR <pr>"),
+   pinning the reviewed head SHA (expected_head_sha) and, where supported,
+   the changed-file set.
+8. Confirm remote master now contains the merge commit (or the expected changes if squash merged).
    *Note: Gitea PR "closed" state is NOT equivalent to "merged". Do not assume a closed PR succeeded without verifying the actual landed changes.*
 
 Then run the cleanup template (worktree-cleanup.md):

skills/llm-project-workflow/templates/review-pr.md

@@ -36,6 +36,11 @@ Steps:
    - Target task role: reviewer identity (must NOT be the PR author)
    *If the current identity does not match the required role (or is the PR author), STOP. Relaunch/switch to the correct profile first.*
 2. Verify your authenticated identity (whoami) and the active profile.
+   Capability evidence (#179): cite the exact gitea_resolve_task_capability
+   output (or runtime context) for review_pr (and merge_pr if merging later);
+   a bare "capability checks passed" claim is downgraded. Stay in the
+   reviewer namespace: any author-namespace call must be justified in the
+   report (#179).
 3. Fetch the PR facts: PR author, head SHA, state (must be open), base branch.
    Pin the head SHA in your notes; every later step validates THAT SHA.
 4. If authenticated user == PR author → STOP (no self-review).
@@ -58,12 +63,23 @@ Steps:
    If HEAD does not match the pinned head → STOP before review/merge.
 7. Confirm the worktree is clean. Inspect the FULL diff; confirm scope matches
    issue #<n>; flag any unrelated files, secrets, or formatting churn. Check that the PR body correctly uses Gitea-closing keywords (`Closes #N` or `Fixes #N`) instead of non-closing ones (`Implements #N`, `Refs #N`).
+   Secret/provenance sweep must be exact (#179): state the exact command,
+   script, grep pattern, or named sweep method AND the scope scanned (e.g.
+   `git diff prgs/master...HEAD | grep -inE '<pattern>'`); "checked the diff
+   for secrets" alone is downgraded.
 8. Run the test suite; report the exact command and exact results — pass/fail
    plus passed/skipped/failed counts, any ignored paths and why they are safe
    to ignore, and whether the command differs from the repository's canonical
    validation command. Only claim a result after the output has been read.
-9. Post the review verdict: approve only if scope is clean and checks pass;
-   otherwise request changes with specifics. Never merge from this review step.
+9. Final live-state recheck (#179), immediately before submitting the review
+   verdict — re-read the live PR and prove:
+   - PR still open
+   - live head SHA still equals the pinned head SHA from step 3
+   - base branch unchanged
+   - no undismissed REQUEST_CHANGES / blocking review state left unaccounted
+   If anything moved → STOP, re-pin, re-validate before any verdict.
+10. Post the review verdict: approve only if scope is clean and checks pass;
+    otherwise request changes with specifics. Never merge from this review step.
    Include a "Review Metadata" block (attribution only — docs/llm-agent-sha.md):
 
    Review Metadata: