Prevent foreign open-PR terminals on the durable review-decision lock from
blocking fresh formal reviews. Scope correction authorization to the named
prior review's PR/head, add read-only diagnosis with exact next_action and
durable handoff payloads, require thread-visible correction audits, and
cover the PR #688 → #692 recovery sequence in regression tests.
Durable review-decision locks (#559) can outlive the PR they protect.
When the last terminal mutation references a PR that is already
merged/closed, expose gitea_cleanup_stale_review_decision_lock so a
reviewer can clear the lock with identity/profile gates and a durable
audit trail — without weakening #332 for open PRs or deleting
session-state files by hand.
Also auto-clear same-profile locks after a successful merge of the
approved PR, and document allowed vs forbidden cleanup.
Closes#594
sysadmin