The plan for the metal-admin leg read 'L3 moves to br-ex', which is false --
do_unlink is called for two different reasons and had one hardcoded. A mutation
log that states the wrong reason is the confident-but-wrong evidence class this
repo keeps paying for.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HvCyrwvYTTcDYnRErfMsNf