e2c34d9553
arc-runner-set pods have no docker daemon and cannot run a privileged DinD sidecar under cluster policy, so Set up Buildx failed to connect to /var/run/docker.sock. Point Buildx at a persistent rootless buildkitd Service (driver: remote, endpoint from the BUILDKIT_ENDPOINT secret) and add its non-privileged Kubernetes manifest. Infra only; no application code changes.