FREE_INSTANCE_REAP_AFTER is set only in docker-compose.site.yml, so a
self-hosted deployment can never reap. Admin and server must carry the
same value: one names the deletion date in warnings, the other acts on it.
Records that admin now has a second control-plane write path, cloudprov,
and that deletion lives in the control plane because that is where the
knowledge of what an instance is made of belongs.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>