Item 4 from the rc.d/release-gate audit. The colibri repo carried its own copy
of scripts/stage-colibri-iso.sh that had drifted behind clawdie-iso's — the ISO
build uses clawdie-iso's copy, and nothing in colibri executes this one, so the
colibri copy was dead split-brain (a maintenance trap). Deleted it and pointed
the PRIORITY-HANDOFF references at clawdie-iso as the canonical owner.
Checks: ./scripts/check-format.sh.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
