fix(apps): always attempt K8s cleanup on delete, cluster service fixes

- Delete endpoint no longer requires clusterId && latestImageTag
- Clusters: getDefault fallback logic, reassign apps on delete
- Unit tests for cluster default/delete logic

backend/src/deployments/deployments.module.ts

@@ -6,7 +6,6 @@ import { Deployment } from './entities/deployment.entity';
 import { ApplicationsModule } from '../applications/applications.module';
 import { KubernetesModule } from '../kubernetes/kubernetes.module';
 import { BuildModule } from '../build/build.module';
-import { SnapshotsModule } from '../snapshots/snapshots.module';
 
 @Module({
   imports: [
@@ -14,7 +13,6 @@ import { SnapshotsModule } from '../snapshots/snapshots.module';
     forwardRef(() => ApplicationsModule),
     KubernetesModule,
     BuildModule,
-    forwardRef(() => SnapshotsModule),
   ],
   controllers: [DeploymentsController],
   providers: [DeploymentsService],