- continuous-improvement: cadence 12h -> hourly.
- add auto-merge-codex workflow: every 15 min, merge open PRs that are
codex-labelled AND from a codex/* branch once all checks are green
(gh pr checks). CI (build/test/lint/harnesses) is the only gate — no
human involvement. Scoped tightly so nothing else auto-merges.
Co-authored-by: Claude <noreply@anthropic.com>