chore(docker): add Dockerfiles and docker-compose for frontend and backend

- Add frontend Dockerfile with multi-stage build using node and nginx
- Add backend Dockerfile with multi-stage build to compile and serve app
- Add docker-compose.yml to define frontend and backend services with environment variables
- Configure nginx to serve SPA, enable gzip compression and caching for static assets
- Set up nginx reverse proxy for API requests to backend service on /api path

nginx.conf

@@ -0,0 +1,31 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Gzip compression
+    gzip on;
+    gzip_types text/plain text/css application/json application/javascript text/xml application/xml;
+
+    # Handle SPA routing
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    # Cache static assets
+    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    # Proxy API requests to backend
+    location /api {
+        proxy_pass http://backend:3001;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection 'upgrade';
+        proxy_set_header Host $host;
+        proxy_cache_bypass $http_upgrade;
+    }
+}