Isolate legacy migration transactions

src/domain/services/legacy-consumer-migration.service.ts

@@ -34,7 +34,10 @@ export class LegacyConsumerMigrationService {
   private readonly circuitRepository = new CircuitRepository();
   private readonly consumerRepository = new ConsumerRepository();
   private readonly roomRepository = new RoomRepository();
-  private readonly migrationRepository = new LegacyConsumerMigrationRepository();
+
+  constructor(
+    private readonly migrationRepository: LegacyConsumerMigrationRepository
+  ) {}
 
   async migrateCircuitList(projectId: string, circuitListId: string): Promise<LegacyMigrationReport> {
     // Migration is additive: legacy consumers are preserved, and circuit-first entities are created