Set DOCKER_HOST, DOCKER_TLS_VERIFY, DOCKER_CERT_PATH for k8s runner
DinD sidecar communication. Add 'until docker info' wait loop to
ensure daemon is ready before build starts.
Co-Authored-By: Claude <noreply@anthropic.com>
Multi-stage Docker build: node:20-alpine + nginx:1.27-alpine.
CI builds and pushes to harbor-in-k3s.cheverjohn.me/iloom/iloom-frontend.
Co-Authored-By: Claude <noreply@anthropic.com>