Merge-time collision gate. Fail-open on util errors (network, auth, bug),
fail-closed on confirmed collisions. pr-title-sync rewrites the PR title
when VERSION changes on push, only for titles that already carry the
v<X.Y.Z.W> prefix (custom titles left alone).
GitLab CI mirrors both jobs for host parity.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Garry Tan