Frontend now publishes its OWN registry image (emi/thermograph-frontend/app)
via build-push.yml and deploys ONLY the frontend service to beta on push to
main, passing SERVICE=frontend + FRONTEND_IMAGE_TAG to infra's deploy.sh.
Independent of the backend's pipeline.
Claude-Session: https://claude.ai/code/session_01RdARHDJaYC1wSQRTYM6t3Z
