refactor(repo): consolidate openflare-server to root and move subprojects to internal/apps

- Merge all files inside openflare-server to the repository root directory.
- Relocate agent, relay, and flared subprojects from internal/ to internal/apps/.
- Combine docker-compose files and update build context paths to root.
- Update GitHub workflows and Dockerfiles to refer to new directories and package names.
- Rewrite Go package imports across all files.
- Resolve database renew test race condition and clean up docs.

frontend/next.config.ts

@@ -0,0 +1,42 @@
+import type {NextConfig} from "next";
+
+const isExport = process.env.NEXT_STANDALONE_EXPORT === 'true';
+
+const nextConfig: NextConfig = {
+  reactCompiler: true,
+  // Prevent 308 redirects on /api/* trailing slashes; dev rewrites proxy legacy APIs as-is.
+  skipTrailingSlashRedirect: true,
+  experimental: {
+  },
+  ...(isExport ? { output: 'export' } : {
+    async redirects() {
+      return [
+        { source: '/openflare', destination: '/', permanent: true },
+        { source: '/openflare/:path*', destination: '/:path*', permanent: true },
+        { source: '/home', destination: '/', permanent: true },
+      ];
+    },
+    async rewrites() {
+      const backendUrl = process.env.WAVELET_BACKEND_URL || 'http://localhost:3000';
+      return [
+        // 上传文件静态资源
+        {
+          source: '/f/:id',
+          destination: `${ backendUrl }/f/:id`,
+        },
+        // robots.txt 路由代理到后端动态接口
+        {
+          source: '/robots.txt',
+          destination: `${ backendUrl }/robots.txt`,
+        },
+        // 标准 RESTful API 接口
+        {
+          source: '/api/:path*',
+          destination: `${ backendUrl }/api/:path*`,
+        }
+      ];
+    },
+  })
+};
+
+export default nextConfig;