Par2 size matching 100x faster; release bookkeeping once per statement

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>

config/gc.ts

@@ -7,6 +7,9 @@ export default {
   /** How often `gc:scheduler` sweeps. */
   intervalMs: env.get('GC_INTERVAL_MS', 3 * 60 * 1000),
 
+  /** How often gc:scheduler recomputes the completeness of releases that changed (LOG.md 2026-10-06 (6)). */
+  releaseCompleteIntervalMs: env.get('RELEASE_COMPLETE_INTERVAL_MS', 30 * 60 * 1000),
+
   jobs: {
     /** Completed jobs are only kept for inspection; keep them briefly. */
     completedAgeSeconds: env.get('GC_COMPLETED_AGE_SECONDS', 60 * 60),