A host can be claimed by a pin as well as by a proxy row, and the proxy-row
check cannot see that. Another account's labeled pin beneath a host makes
the host its cluster, so a self-addressed endpoint on it would never be
served; another account's self-addressed endpoint on a host makes the proxy
declaring it theirs, so a label beneath it would never be served either.
Both bootstrap paths now refuse those shapes before the insert.
Neither question touches the shared-cluster shape: labeled pins under one
cluster are asked about in neither direction, so any number of accounts
still pin beneath a shared cluster. Two self-addressed endpoints on one
hostname stay the domain unique index's conflict to refuse.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Sa3DsBDP3VciAi4PPG17L6
