fix(mining-admin-web): prevent duplicate /api/v2 in rewrite destination

Clean NEXT_PUBLIC_API_URL to remove trailing /api/v2 if present,
preventing paths like /api/v2/api/v2/configs/mining/status

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/mining-admin-web/next.config.js

@@ -3,10 +3,15 @@ const nextConfig = {
   reactStrictMode: true,
   output: 'standalone',
   async rewrites() {
+    // NEXT_PUBLIC_API_URL 应该是后端服务的基础 URL，如 http://mining-admin-service:3023
+    // 前端请求 /api/xxx 会被转发到 {API_URL}/api/v2/xxx
+    const apiBaseUrl = process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3023';
+    // 移除末尾可能存在的 /api/v2 避免重复
+    const cleanUrl = apiBaseUrl.replace(/\/api\/v2\/?$/, '');
     return [
       {
         source: '/api/:path*',
-        destination: `${process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3023'}/api/v2/:path*`,
+        destination: `${cleanUrl}/api/v2/:path*`,
       },
     ];
   },