Rebuild: sort indexes that match newest-first

The default page (no search words) took 23-27 s: SearchService sorts
posted_at DESC NULLS LAST, id DESC, the indexes were on posted_at DESC
(nulls first), so Postgres sorted all 68M releases. New indexes match
the sort (also per category), built concurrently; the old ones dropped.

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

database/migrations/1770000002000_releases_sort_indexes.ts

@@ -0,0 +1,25 @@
+import { BaseSchema } from '@adonisjs/lucid/schema'
+
+/**
+ * Indexes that match the newest-first sort (SearchService: posted_at DESC
+ * NULLS LAST, id DESC). The old ones (posted_at DESC: nulls first) didn't,
+ * so the default page sorted all 68M releases: 23 s. Built concurrently, the
+ * old ones dropped after.
+ */
+export default class extends BaseSchema {
+  static disableTransactions = true
+
+  async up() {
+    this.schema.raw(`CREATE INDEX CONCURRENTLY IF NOT EXISTS releases_newest_idx ON releases (posted_at DESC NULLS LAST, id DESC)`)
+    this.schema.raw(`CREATE INDEX CONCURRENTLY IF NOT EXISTS releases_category_newest_idx ON releases (category, posted_at DESC NULLS LAST, id DESC)`)
+    this.schema.raw(`DROP INDEX CONCURRENTLY IF EXISTS releases_posted_at_idx`)
+    this.schema.raw(`DROP INDEX CONCURRENTLY IF EXISTS releases_category_posted_idx`)
+  }
+
+  async down() {
+    this.schema.raw(`CREATE INDEX CONCURRENTLY IF NOT EXISTS releases_posted_at_idx ON releases (posted_at DESC)`)
+    this.schema.raw(`CREATE INDEX CONCURRENTLY IF NOT EXISTS releases_category_posted_idx ON releases (category, posted_at DESC)`)
+    this.schema.raw(`DROP INDEX CONCURRENTLY IF EXISTS releases_newest_idx`)
+    this.schema.raw(`DROP INDEX CONCURRENTLY IF EXISTS releases_category_newest_idx`)
+  }
+}