fix(database): tolerate retried v14 migration

test/database/app_database_test.dart

@@ -1,3 +1,5 @@
+import 'dart:io';
+
 import 'package:drift/drift.dart' hide isNull, isNotNull;
 import 'package:drift/native.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -106,6 +108,34 @@ class _AppDatabaseTestSuite {
           containsAll(['idx_profiles_kind', 'idx_profile_connections_profile_id', 'idx_offline_watch_progress_server']),
         );
       });
+
+      test('retried v14 migration tolerates existing indices', () async {
+        await db.close();
+        final tempDir = await Directory.systemTemp.createTemp('plezy_db_migration_test_');
+        final file = File('${tempDir.path}/plezy_downloads.db');
+        AppDatabase? seeded;
+        AppDatabase? reopened;
+
+        try {
+          seeded = AppDatabase.forTesting(NativeDatabase(file));
+          await seeded.select(seeded.connections).get();
+          await seeded.customStatement('PRAGMA user_version = 13');
+          await seeded.close();
+          seeded = null;
+
+          reopened = AppDatabase.forTesting(NativeDatabase(file));
+          expect(await reopened.select(reopened.connections).get(), isEmpty);
+          final rows = await reopened
+              .customSelect("SELECT name FROM sqlite_master WHERE type = 'index' AND name = 'idx_connections_kind'")
+              .get();
+          expect(rows, hasLength(1));
+        } finally {
+          await reopened?.close();
+          await seeded?.close();
+          await tempDir.delete(recursive: true);
+          db = AppDatabase.forTesting(NativeDatabase.memory());
+        }
+      });
     });
   }