chore: simplify email-worker Docker setup

Remove private registry references and SSH key handling from Docker
build process. Images now build locally without registry prefix.

Changes:
- Remove SSH key copying from Dockerfile (no private npm packages)
- Remove registry.ngit.hr references from build and run scripts
- Simplify image tags to local format (no registry prefix)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

email-worker/run-image.sh

@@ -6,7 +6,7 @@ if [ "$1" == "" ] ; then
     exit 1
 fi
 
-IMAGE_TAG=pr-d-registry.ngit.hr/ngit/evo-open-table-sync-svc:$1
+IMAGE_TAG=evo-open-table-sync-svc:$1
 
 docker run -p 3000:3000 \
    --env DEBUG=* \