fix 502

frontend/server.cjs

@@ -0,0 +1,25 @@
+const express = require('express');
+const { createProxyMiddleware } = require('http-proxy-middleware');
+const path = require('path');
+
+const app = express();
+
+// API 代理
+app.use('/api', createProxyMiddleware({
+  target: 'http://backend:3001',
+  changeOrigin: true,
+}));
+
+// 静态文件服务
+const staticPath = path.join(__dirname, 'dist');
+app.use(express.static(staticPath));
+
+// 处理所有其他路由，返回 index.html
+app.get('*', (req, res) => {
+  res.sendFile(path.join(staticPath, 'index.html'));
+});
+
+const port = process.env.PORT || 3000;
+app.listen(port, '0.0.0.0', () => {
+  console.log(`Server is running on port ${port}`);
+});