A config knob for what a PR approval does: "may merge" vs "merged"

Kind: enhancement · Source: e2e Slack test 2026-09-19 (O9) · Not fixed in issue-393

What was seen

After a Slack "approved" satisfied human-approval, the session merged PR #<n> within 21 seconds and closed the issue, with zero GitHub reviews on the PR. The Slack "approved" was the human PR approval the tier requires, so this is consistent with the tier rules — but:

a repository with branch protection would have refused the merge; and
some teams will want "approved" to mean "you may merge" rather than "merged now".

Suggested change (from the report)

A config knob, or at least a line in the approval request saying what approving will do:

an option where human-approval means "the-loop may merge" (it merges) vs. "the human will merge" (the-loop stops at approved and leaves the merge to a person / branch protection); and/or
the approval request message stating plainly, before the tap, that approving will merge and close.

Acceptance

An operator can configure whether an approval merges the PR or only marks it approved, and the approval request says which behaviour is in effect; branch protection is respected rather than hit as a surprise.

Note

Lower priority than the bugs — current behaviour is correct per the tier rules, this is about making the consequence explicit and configurable.

Fixed (branch `fix/n1-selection-grammar-refusal-reason`)

A routing.mergeOnApproval config knob (default true, the pre-O9 behaviour) now governs what a human-approval approval does: true merges and closes, false stops at approved and leaves the merge to a person / branch protection. The pr-review-pending message states which behaviour is in effect before the tap ("Approving will merge this PR and close the work item." vs "Approving marks it approved; a person merges it (branch protection and required reviews still apply)."). The schema documents the knob, and the-loop skill (SKILL.md) tells the session to honour it and never merge when it is false. Tests in test_bus_integration.py cover both messages.