Fix CLI workflow and container startup

- Updated GitHub Actions workflow to call `infinito make ...` inside container
- Simplified Dockerfile CMD to run `infinito --help` and keep container alive
- Adjusted docker-compose.yml to use explicit image name

See: https://chatgpt.com/share/68cde606-c3f8-800f-8ac5-fc035386da87

docker-compose.yml

@@ -8,8 +8,8 @@ services:
       network: host
     pull_policy: never
     container_name: infinito_nexus
+    image: infinito_nexus
     restart: unless-stopped
-    command: tail -f /dev/null
     volumes:
       - data:/var/lib/docker/volumes/
       - backups:/Backups/