重构后端，改为 node 技术栈

backend/src/app.js

@@ -0,0 +1,57 @@
+/**
+ * 入口文件 — 对应 Python: main.py
+ */
+require('dotenv').config({ override: true });
+
+const express = require('express');
+const cors = require('cors');
+const sequelize = require('./config/database');
+const logger = require('./config/logger');
+const routes = require('./routes');
+const { bodyLimit } = require('./middleware/bodyLimit');
+
+const app = express();
+
+// 中间件
+app.use(cors({ origin: '*', credentials: true }));
+app.use(express.json());
+app.use(express.urlencoded({ extended: true }));
+app.use(bodyLimit);
+
+// 根路径（无需登录）
+app.get('/', (req, res) => {
+  res.json({
+    message: '欢迎使用 Audio Dashboard API',
+    docs: '/docs',
+    redoc: '/redoc',
+  });
+});
+
+// 健康检查（无需登录）
+app.get('/health', (req, res) => {
+  res.json({ status: 'healthy' });
+});
+
+// 业务路由（需登录的路由在各自文件中挂载 authMiddleware）
+routes.forEach((r) => app.use(r));
+
+// 同步数据库并启动
+const PORT = process.env.PORT || 8083;
+
+async function start() {
+  try {
+    logger.info('Creating database tables...');
+    await sequelize.sync();
+    logger.info('Database tables created successfully');
+  } catch (e) {
+    logger.error(`Warning: Could not create tables: ${e.message}`);
+    logger.error('Continuing without table creation...');
+  }
+
+  app.listen(PORT, '0.0.0.0', () => {
+    logger.info(`Server running on http://localhost:${PORT}`);
+    logger.info(`API docs: http://localhost:${PORT}/docs`);
+  });
+}
+
+start();