Configure for self-hosted deployment

- Add environment variable support for Supabase and Pakasir configurations
- Create Docker configuration with Nginx for production deployment
- Add .env.example with all required environment variables
- Remove hardcoded URLs from Supabase client and Checkout component
- Add Docker and Nginx configuration files for Coolify deployment

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

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

nginx.conf

@@ -0,0 +1,64 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Enable gzip compression
+    gzip on;
+    gzip_vary on;
+    gzip_min_length 1024;
+    gzip_proxied expired no-cache no-store private must-revalidate auth;
+    gzip_types
+        text/plain
+        text/css
+        text/xml
+        text/javascript
+        application/javascript
+        application/xml+rss
+        application/json;
+
+    # Security headers
+    add_header X-Frame-Options "SAMEORIGIN" always;
+    add_header X-Content-Type-Options "nosniff" always;
+    add_header X-XSS-Protection "1; mode=block" always;
+    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
+
+    # Cache static assets
+    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+        access_log off;
+    }
+
+    # Cache HTML files for shorter time
+    location ~* \.html$ {
+        expires 1h;
+        add_header Cache-Control "public, must-revalidate";
+    }
+
+    # Handle React Router - try to serve file, fallback to index.html
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    # API proxy (if needed for local development)
+    # location /api/ {
+    #     proxy_pass http://backend:3000/;
+    #     proxy_http_version 1.1;
+    #     proxy_set_header Upgrade $http_upgrade;
+    #     proxy_set_header Connection 'upgrade';
+    #     proxy_set_header Host $host;
+    #     proxy_set_header X-Real-IP $remote_addr;
+    #     proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    #     proxy_set_header X-Forwarded-Proto $scheme;
+    #     proxy_cache_bypass $http_upgrade;
+    # }
+
+    # Error pages
+    error_page 404 /index.html;
+    error_page 500 502 503 504 /50x.html;
+    location = /50x.html {
+        root /usr/share/nginx/html;
+    }
+}