feat: add Docker deployment support

- Add multi-stage Dockerfile for Next.js standalone build
- Add docker-compose.yml with app and MySQL 8.0 services
- Add .dockerignore for optimized builds
- Update next.config.ts with standalone output

next.config.ts

@@ -1,7 +1,7 @@
 import type { NextConfig } from "next";
 
 const nextConfig: NextConfig = {
-  /* config options here */
+  output: "standalone",
 };
 
 export default nextConfig;