feat: implement SSL support with Let's Encrypt and update Nginx configuration

docker-compose.yml

@@ -122,13 +122,23 @@ services:
     image: nginx:alpine
     ports:
       - "80:80"
+      - "443:443"
     volumes:
       - ./nginx/nginx.conf:/etc/nginx/conf.d/default.conf:ro
+      - ./certbot/www:/var/www/certbot:ro
+      - ./certbot/conf:/etc/letsencrypt:ro
     depends_on:
       - backend
       - frontend
     restart: unless-stopped
 
+  # --- Certbot (Let's Encrypt) ---
+  certbot:
+    image: certbot/certbot
+    volumes:
+      - ./certbot/www:/var/www/certbot
+      - ./certbot/conf:/etc/letsencrypt
+
 volumes:
   redis_data:
   upload_data: