Test-only approval commit after the 955581c main merge (sw-test-regression-
baseline section 9); no protected path changes, no Story change.
- approvedMainCommit f340a26 -> 955581c.
- public-api.approved.json kept: the public .d.ts files are byte-identical.
- docs/sw/sw-viewer-button-height-2026-10-21.md: change and verification.
