feat: 实现RCU升级后端服务初始版本

- 添加Kafka消费者组件用于消费升级事件数据
- 实现数据处理器进行数据验证和转换
- 添加数据库写入组件支持批量写入G5数据库
- 配置环境变量管理连接参数
- 添加日志记录和错误处理机制
- 实现优雅关闭和流控功能

bls-upgrade-backend/package.json

@@ -0,0 +1,28 @@
+{
+  "name": "bls-upgrade-backend",
+  "version": "1.0.0",
+  "type": "module",
+  "private": true,
+  "scripts": {
+    "dev": "node src/index.js",
+    "dev:test-consumer": "node src/test-consumer.js",
+    "build": "vite build --ssr src/index.js --outDir dist",
+    "test": "vitest run",
+    "lint": "node scripts/lint.js",
+    "spec:lint": "openspec validate --specs --strict --no-interactive",
+    "spec:validate": "openspec validate --specs --no-interactive",
+    "start": "node dist/index.js"
+  },
+  "dependencies": {
+    "dotenv": "^16.4.5",
+    "kafka-node": "^5.0.0",
+    "node-cron": "^4.2.1",
+    "pg": "^8.11.5",
+    "redis": "^4.6.13",
+    "zod": "^4.3.6"
+  },
+  "devDependencies": {
+    "vite": "^5.4.0",
+    "vitest": "^4.0.18"
+  }
+}