feat: Add Docker configuration for the Next.js frontend, enabling standalone output and next-intl integration.

frontend/next.config.ts

@@ -1,7 +1,9 @@
 import type { NextConfig } from "next";
 import createNextIntlPlugin from 'next-intl/plugin';
 
-const nextConfig: NextConfig = {};
+const nextConfig: NextConfig = {
+    output: "standalone",
+};
 const withNextIntl = createNextIntlPlugin();
 
 export default withNextIntl(nextConfig);