feat(GOV-009): 建立后端契约与健康检查

server/apps/api/src/health.controller.ts

@@ -0,0 +1,22 @@
+import { Controller, Get, HttpException, HttpStatus, Inject } from '@nestjs/common';
+import { ApiOkResponse, ApiServiceUnavailableResponse, ApiTags } from '@nestjs/swagger';
+
+import { HealthResponseDto } from '../../../libs/http-contracts/src/health.dto';
+import { HealthService } from './health.service';
+
+@ApiTags('health')
+@Controller('health')
+export class HealthController {
+  constructor(@Inject(HealthService) private readonly healthService: HealthService) {}
+
+  @Get()
+  @ApiOkResponse({ type: HealthResponseDto })
+  @ApiServiceUnavailableResponse({ type: HealthResponseDto })
+  async getHealth(): Promise<HealthResponseDto> {
+    const response = await this.healthService.check();
+    if (response.status === 'unavailable') {
+      throw new HttpException(response, HttpStatus.SERVICE_UNAVAILABLE);
+    }
+    return response;
+  }
+}