Closes#9.
Three pieces, all small:
1. **docs/e2e-coverage.md** — source of truth for which E2E suites
guard which surfaces. Today three were running but informational
only on staging; that's how the org-import silent-drop bug shipped
without a test catching it pre-merge. Now the matrix shows what's
required where + a follow-up note for the two suites that need an
always-emit refactor before they can be required.
2. **tools/branch-protection/apply.sh** — branch protection as code.
Lets `staging` and `main` required-checks live in a reviewable
shell script instead of UI clicks that get lost between admins.
This PR's net change: add `E2E API Smoke Test` and `Canvas tabs E2E`
as required on staging. Both already use the always-emit path-filter
pattern (no-op step emits SUCCESS when the workflow's paths weren't
touched), so making them required can't deadlock unrelated PRs.
3. **branch-protection-drift.yml** — daily cron + drift_check.sh
that compares live protection against apply.sh's desired state.
Catches out-of-band UI edits before they drift further. Fails the
workflow on mismatch; ops re-runs apply.sh or updates the script.
Out of scope (filed as follow-ups):
- e2e-staging-saas + e2e-staging-external use plain `paths:` filters
and never trigger when paths are unchanged. They need refactoring
to the always-emit shape (same as e2e-api / e2e-staging-canvas)
before they can be required.
- main branch protection mirrors staging here; if main wants the
E2E SaaS / External added later, do it in apply.sh and rerun.
Operator must apply once after merge:
bash tools/branch-protection/apply.sh
The drift check picks it up from there.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>