The required Browser harness check comes from a job that needs: build, so for
a moment per push every registered check is green and GitHub says
MERGEABLE/BLOCKED. #186 at 128a2a0 refused that and exited 1 on healthy PRs.
BLOCKED with no failed check is now waited on (exit 3 if it never clears).
Adds the gap sequence from PR #189's real rollup, and a head moving during
the UNKNOWN wait. Corrects tooling.md's claim that nothing else produces
BLOCKED, the evidence entry's rival-2 claims, and the fixture wording.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze
Edward Langley
a4fa3ae174