merge-queue-or-shadow-branch

name	merge-queue-or-shadow-branch
description	Prefer GitHub merge queue; otherwise test-merge through integration/codex before merging.

Merge Queue Or Shadow Branch

Order:

1. Use GitHub merge queue when enabled and practical.
2. Otherwise reset integration/codex to origin/main.
3. Merge the candidate head into integration/codex.
4. Run Captain verification.
5. Merge the original PR only with expected head SHA match.