fix: use custom Dockerfile for gimp-mcp with correct entrypoint

- Move gimp-mcp Dockerfile to tracked dockerfiles/ directory
- Update entrypoint from uvx gimp-mcp to uvx gimp-mcp-server
- Add uv.lock to dependency copy step
- Update docker-compose.yml to use dockerfiles/gimp-mcp/Dockerfile

docker-compose.yml

@@ -323,7 +323,7 @@ services:
     image: kneldevstack-aimiddleware-gimp-mcp
     build:
       context: ./vendor/gimp-mcp
-      dockerfile: Dockerfile
+      dockerfile: ../../dockerfiles/gimp-mcp/Dockerfile
     container_name: kneldevstack-aimiddleware-gimp-mcp
     restart: unless-stopped
     environment: