Replace individual `docker run` commands with Docker Compose stack managed
by systemd. Nginx now fronts all 5 registry ports (5000/5010/5020/5030/5040)
with proxy_cache_lock to serialize concurrent blob pulls and prevent
corrupt partial responses. Adds QEMU guest agent for remote management.
Replace deprecated wildcard containerd mirror with per-registry
config_path approach. Add proxy containers for ghcr.io, quay.io,
registry.k8s.io, and reg.kyverno.io on the docker-registry VM.
Set static IP for docker-registry VM to avoid DHCP issues.
