Enforce single terminal review decision per PR review run (Issue #211)

Reviewer agents could post probe APPROVE/REQUEST_CHANGES reviews while
testing lock paths, polluting PR audit trails. Add a review decision lock
seeded by gitea_resolve_task_capability(review_pr) that requires
gitea_mark_final_review_decision and final_review_decision_ready=True
before gitea_submit_pr_review performs a live mutation.

Add gitea_dry_run_pr_review for read-only submission validation,
gitea_authorize_review_correction for operator-approved fixes, and
assess_review_mutation_final_report for final-report proof. One live
review mutation per run unless correction is explicitly authorized.

skills/llm-project-workflow/SKILL.md

@@ -231,6 +231,15 @@ Worktree folder = branch with `/` replaced by `-`
    differs from the repository's canonical validation command. Only claim a
    validation result after the command has completed and its output has
    been read (`review_proofs.assess_validation_report`).
+   During validation, review work is **read-only**: use
+   `gitea_dry_run_pr_review` to prove submission mechanics — never post live
+   APPROVE, REQUEST_CHANGES, or review comments to probe tool paths. After
+   validation completes, call `gitea_mark_final_review_decision`, then submit
+   exactly one live review via
+   `gitea_submit_pr_review(..., final_review_decision_ready=True)`.
+   Final reports must list exactly one review mutation
+   (`review_proofs.assess_review_mutation_final_report`) unless an
+   operator-approved correction flow was invoked and explained.
 10. **Do not merge if checks fail. Do not merge if the reviewer is the author.**
 11. The final report must distinguish (`review_proofs.build_final_report`):
     identity eligible; PR author different from reviewer; session