fix: 配置 Next.js 静态导出解决 CI/CD 部署问题

- 在 next.config.mjs 中添加 output: 'export' 配置
- 设置 distDir: 'out' 指定输出目录
- 添加 trailingSlash: true 优化静态文件服务
- 现在构建会生成 frontend/out 目录供 CI/CD 部署使用

修复了 rsync 找不到 frontend/out 目录的问题

frontend/tsconfig.json

@@ -1,6 +1,10 @@
 {
   "compilerOptions": {
-    "lib": ["dom", "dom.iterable", "esnext"],
+    "lib": [
+      "dom",
+      "dom.iterable",
+      "esnext"
+    ],
     "allowJs": true,
     "target": "ES6",
     "skipLibCheck": true,
@@ -19,9 +23,19 @@
       }
     ],
     "paths": {
-      "@/*": ["./*"]
+      "@/*": [
+        "./*"
+      ]
     }
   },
-  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],
-  "exclude": ["node_modules"]
+  "include": [
+    "**/*.ts",
+    "**/*.tsx",
+    ".next/types/**/*.ts",
+    "next-env.d.ts",
+    "out/types/**/*.ts"
+  ],
+  "exclude": [
+    "node_modules"
+  ]
 }