The buildkit builder in the k8s runner cannot pull FROM the artifactapi
registry (internal CA is not trusted). Keep the base-image FROM on gitea;
only the push target moves to artifactapi.
Claude-Session: https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv
Hard switch of the docker push target from the Gitea registry to the
artifactapi local docker registry (docker-internal); the Gitea VM and its
registry are being retired. Drops the droneci/DRONECI_PASSWORD creds since
artifactapi accepts unauthenticated in-cluster pushes. Also repoints the Dockerfile FROM agent-base base image.
Claude-Session: https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv