matchPar2Releases checked every same-size release_files row's set and
date (18 s per batch of body-derived binaries); now an index on
release_files (release_id, size) drops the repeated sizes first: 0.16 s.
File inserts updated their release in four row triggers; one statement
trigger now updates each release once per INSERT. Completeness is noted
in release_dirty and recomputed by gc:scheduler every 30 minutes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
