Reserve grafana/prometheus/flux alongside rancher during rebuild cleanup so
stale tailnet devices do not force -1 hostnames. Tag the exposed Tailscale
services so operator-managed proxies are provisioned with explicit prod/service
tags from the tailnet policy.
Replace Ansible port-forwarding + tailscale serve with direct Tailscale LB
services matching the existing Rancher pattern. Each service gets its own
tailnet hostname (grafana/prometheus/flux.silverside-gopher.ts.net).
