FileGRC 0.21.5

Fix validation of finalized meeting proof with distinct agenda and minutes. Each Markdown companion now compares against its own committed section, while edits, removals, and additions after finalization remain protected.

Keep URL pushes synchronized on Git 2.56 while bounding local tracking-ref updates. A ref already at the pushed commit is accepted atomically; a different concurrent ref still requires reconciliation and cannot be retried as an unconfirmed push.

No data-model migration or program-record changes are required.