perf: Add trigram index for doc title search (outline#8454)

Author: tommoor

server/migrations/20250217012609-document-title-index.js

@@ -0,0 +1,19 @@
+'use strict';
+
+/** @type {import('sequelize-cli').Migration} */
+module.exports = {
+async up (queryInterface) {
+    await queryInterface.sequelize.query(
+      `CREATE EXTENSION IF NOT EXISTS "pg_trgm";`,
+    );
+    await queryInterface.sequelize.query(
+      `CREATE INDEX CONCURRENTLY documents_title_idx ON documents USING GIN (title gin_trgm_ops);`,
+    );
+  },
+
+  async down (queryInterface) {
+    await queryInterface.sequelize.query(
+      `DROP INDEX CONCURRENTLY documents_title_idx;`,
+    );
+  }
+};