chore(docker): use local bind mount for uploads

Store uploaded files under data/uploads for both the app and Caddy instead of the named Docker volume. Update .gitignore to keep runtime data out of Git while preserving the uploads directory placeholder.

docker-compose.yml

@@ -28,7 +28,7 @@ services:
     expose:
       - "3000"
     volumes:
-      - uploads:/app/public/uploads
+      - ./data/uploads:/app/public/uploads
 
   mailpit:
     image: axllent/mailpit:latest
@@ -46,7 +46,7 @@ services:
       - ./Caddyfile:/etc/caddy/Caddyfile:ro
       - ./data/caddy/data:/data
       - ./data/caddy/config:/config
-      - uploads:/srv/uploads
+      - ./data/uploads:/srv/uploads
     depends_on:
       - app
 
@@ -59,5 +59,3 @@ services:
     profiles:
       - dev
 
-volumes:
-  uploads: