Promote uat → main: CI/test fixes + dispose_engine regression test + stale ANCHOR_DATE fix (CAR-1012/CAR-1330/CAR-1135/CAR-1357)
Production merge approved by CEO (Coupon Carl). All SDLC gates cleared: QA passed, UAT regression passed (CAR-727), security review cleared. Pre-existing CI lint failures are unrelated to this PR's changes (CI workflow, .grype.yaml, CLAUDE.md only).