infra: add persistent uploads volume and configure Caddy to serve static images

- Add named Docker volume `uploads` mounted at /app/public/uploads in app container
- Share same volume with Caddy at /srv/uploads for direct static file serving
- Add Caddy `handle /uploads/*` block so images bypass Next.js (standalone mode does not serve runtime public files)
- Create uploads directory with correct nextjs:nodejs ownership in Dockerfile
- Add mkdir safeguard in entrypoint.sh

docker-compose.yml

@@ -27,6 +27,8 @@ services:
       DATABASE_URL: postgresql://ecommerce:ecommerce_password@db:5432/ecommerce
     expose:
       - "3000"
+    volumes:
+      - uploads:/app/public/uploads
 
   mailpit:
     image: axllent/mailpit:latest
@@ -44,6 +46,7 @@ services:
       - ./Caddyfile:/etc/caddy/Caddyfile:ro
       - caddy_data:/data
       - caddy_config:/config
+      - uploads:/srv/uploads
     depends_on:
       - app
 
@@ -51,3 +54,4 @@ volumes:
   pgdata:
   caddy_data:
   caddy_config:
+  uploads: