Fold only sidecar-only releases (sidecar_only at insert); no queue-wide scan for gone releases

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

database/migrations/1770000004200_releases_sidecar_only.ts

@@ -0,0 +1,16 @@
+import { BaseSchema } from '@adonisjs/lucid/schema'
+
+/**
+ * releases.sidecar_only: set by the batch store when it inserts a small release (at most 3 files, under 1 MB) whose
+ * files are all sidecars (.nfo, .sfv, .nzb, …). The settler queues only those for the sidecar fold: it queued every
+ * small release, 13.5M (single images mostly), and the fold's queue scans held the merger back (LOG.md 2026-10-17 (72)).
+ */
+export default class extends BaseSchema {
+  async up() {
+    this.schema.raw(`ALTER TABLE releases ADD COLUMN IF NOT EXISTS sidecar_only boolean`)
+  }
+
+  async down() {
+    this.schema.raw(`ALTER TABLE releases DROP COLUMN IF EXISTS sidecar_only`)
+  }
+}