feat: 实现ID生成器并重构模型ID生成逻辑

refactor: 统一ID生成方式，使用新的idGenerator模块
refactor: 重构模型ID生成逻辑，允许空ID并在创建前自动生成
fix(roomSchema): 使机房ID字段变为可选并更新前端表单验证
style: 格式化代码并优化导入语句
test: 添加操作日志集成测试文件
docs: 添加错误处理模块文档

backend/routes/auth.js

@@ -11,13 +11,10 @@ const {
   USERNAME_MIN_LENGTH,
   USERNAME_MAX_LENGTH,
 } = require('../config');
+const { generateId } = require('../utils/idGenerator');
 
 const router = express.Router();
 
-const generateId = () => {
-  return 'user_' + Date.now().toString(36) + Math.random().toString(36).substr(2, 9);
-};
-
 router.post('/register', async (req, res) => {
   try {
     const { username, password, email, phone, realName } = req.body;
@@ -57,7 +54,7 @@ router.post('/register', async (req, res) => {
     const isFirstUser = userCount === 0;
 
     const user = await User.create({
-      userId: generateId(),
+      userId: generateId({ prefix: 'USR' }),
       username,
       password: hashedPassword,
       email,