fix: update Docker image name to match erp-mafia org

Repo moved from gnubok/gnubok to erp-mafia/erp-base. Updated GHCR image
reference in CI workflow and docker-compose.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/docker-publish.yml

@@ -6,7 +6,7 @@ on:
 
 env:
   REGISTRY: ghcr.io
-  IMAGE_NAME: gnubok/gnubok
+  IMAGE_NAME: erp-mafia/erp-base
 
 jobs:
   build-and-push: