feat(deploy): remove cluster allocation section from app creation

Drop the admin-only "cluster assignment" UI from the resources &
config step of the deploy wizard and the related backend override.
App placement is now always decided automatically by the allocator.

- frontend: remove cluster/pool selection block, review-step cluster
  row, clusterMode state, public cluster/pool queries, and clusterId/
  poolId from CreateApplicationDto
- backend: drop clusterId/poolId override from the create DTO and
  simplify ApplicationsService.create to always auto-allocate; widen
  selectClusterForApplication param to keep the fallback path working

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/src/applications/applications.controller.ts

@@ -63,7 +63,7 @@ export class ApplicationsController {
   @Post()
   @ApiOperation({ summary: 'Create a new application' })
   async create(@Request() req: any, @Body() dto: CreateApplicationDto) {
-    return this.applicationsService.create(req.user.id, dto, req.user.role);
+    return this.applicationsService.create(req.user.id, dto);
   }
 
   @Post(':id/upload')

backend/src/applications/applications.service.ts

@@ -9,7 +9,6 @@ import { Application } from './entities/application.entity';
 import { CreateApplicationDto, UpdateApplicationDto } from './dto/application.dto';
 import { ClustersService } from '../clusters/clusters.service';
 import {
-  UserRole,
   DatabaseType,
   CustomDomainStatus,
   AppRuntime,
@@ -57,39 +56,17 @@ export class ApplicationsService {
     throw new BadRequestException('Failed to generate a unique subdomain. Please try again.');
   }
 
-  async create(userId: string, dto: CreateApplicationDto, userRole?: string): Promise<Application> {
+  async create(userId: string, dto: CreateApplicationDto): Promise<Application> {
     dto = normalizeCreateApplicationDto(dto);
     const productType = dto.productType ?? ProductType.APPLICATION;
 
-    // End users and technical staff cannot influence placement; only admins may manually assign.
-    const isAdmin = userRole === UserRole.ADMIN;
-    if (!isAdmin) {
-      if (dto.clusterId || dto.poolId) {
-        this.logger.warn(`Non-admin user ${userId} attempted manual cluster/pool selection - ignoring`);
-      }
-      dto.clusterId = undefined;
-      dto.poolId = undefined;
-    }
-
-    let clusterId = dto.clusterId;
-    let poolId = dto.poolId;
-    let allocationLogId: string | undefined;
-
-    if (isAdmin && clusterId) {
-      await this.clustersService.findOne(clusterId);
-      this.logger.log(`Manual cluster assignment for app "${dto.name}" -> cluster ${clusterId}`);
-    } else {
-      const allocationDto = { ...dto };
-      if (poolId) {
-        allocationDto.poolId = poolId;
-      }
-      const allocation = await this.clustersService.selectClusterForApplication(allocationDto, userId);
-      clusterId = allocation.cluster.id;
-      poolId = allocation.pool?.id || (isAdmin ? poolId : undefined);
-      allocationLogId = allocation.allocationLogId;
-      if (!clusterId) {
-        throw new BadRequestException('No eligible cluster available for this application');
-      }
+    // Placement is always decided automatically by the allocator.
+    const allocation = await this.clustersService.selectClusterForApplication(dto, userId);
+    const clusterId = allocation.cluster.id;
+    const poolId = allocation.pool?.id;
+    const allocationLogId = allocation.allocationLogId;
+    if (!clusterId) {
+      throw new BadRequestException('No eligible cluster available for this application');
     }
 
     // Generate database credentials if a database is requested

backend/src/applications/dto/application.dto.ts

@@ -198,16 +198,6 @@ export class CreateApplicationDto {
   @IsNumber()
   port?: number;
 
-  @ApiPropertyOptional({ description: 'Admin-only manual cluster override. Ignored for non-admin users.' })
-  @IsOptional()
-  @IsString()
-  clusterId?: string;
-
-  @ApiPropertyOptional({ description: 'Admin-only pool override. Ignored for non-admin users.' })
-  @IsOptional()
-  @IsString()
-  poolId?: string;
-
   @ApiPropertyOptional({ example: 'www.example.com', description: 'Custom domain for the application (requires additional fee)' })
   @IsOptional()
   @IsString()

backend/src/clusters/clusters.service.ts

@@ -266,7 +266,7 @@ export class ClustersService implements OnModuleInit, OnModuleDestroy {
   }
 
   async selectClusterForApplication(
-    dto: CreateApplicationDto,
+    dto: CreateApplicationDto & { poolId?: string },
     userId: string,
     options: {
       excludeClusterIds?: string[];