Add Docker-based production deployment

- Multi-stage Dockerfile with Node builder and nginx server
- Nginx configuration with gzip, security headers, and caching
- Docker Compose setup with health checks
- Updated README with deployment instructions

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

README.md

@@ -26,6 +26,48 @@ npm run build
 
 The built files will be in the `dist/` directory.
 
+## Docker Deployment
+
+### Using Docker Compose (Recommended)
+
+```bash
+# Build and start the container
+docker-compose up -d
+
+# View logs
+docker-compose logs -f
+
+# Stop the container
+docker-compose down
+```
+
+The game will be available at `http://localhost:8080`
+
+### Using Docker directly
+
+```bash
+# Build the image
+docker build -t whalehunting-game .
+
+# Run the container
+docker run -d -p 8080:80 --name whalehunting whalehunting-game
+
+# View logs
+docker logs -f whalehunting
+
+# Stop and remove container
+docker stop whalehunting
+docker rm whalehunting
+```
+
+### Production Deployment Notes
+
+- The Docker image uses nginx to serve static files
+- Includes gzip compression for better performance
+- Health checks are configured for container monitoring
+- Security headers are enabled
+- Static assets are cached for 1 year
+
 ## Project Structure
 
 ```