优化: 大文件拆分+代码分割+按需加载+console清理+any类型替换

- Money.tsx (2260行→54行): 拆分为 money/ 子目录4个组件, React.lazy二级分割
- AIAssistant.tsx (2038行→63行): 拆分为 ai-assistant/ 子目录6个组件, React.lazy二级分割
- xlsx改为动态导入, OvertimeTab从345KB降至12.7KB
- api-services.ts: 请求参数 any→Record<string,unknown>
- 移除前端3处console.log残留
- 后端console替换为pino logger
- 前后端未使用import/变量清理
- Zod schema验证: termination/platform/special-status/work-process
- 新增 leave.routes.ts, acceptance-test.routes.ts
- UI组件: PageGuide, QueryError, Stepper

backend/package.json

@@ -29,6 +29,8 @@
     "multer": "^2.2.0",
     "node-cron": "^3.0.3",
     "openai": "^6.48.0",
+    "pino": "^10.3.1",
+    "pino-pretty": "^13.1.3",
     "redis": "^6.1.0",
     "uuid": "^10.0.0",
     "xlsx": "^0.18.5",