Stability checkpoint — release-please disabled (GitHub-only tool) + Phase Q-2 + Phase B-3 Post-merge main pipeline #662 green (2026-04-22 ~14:55). MR !140: diagnose + disable release-please CI job (googleapis tool is GitHub-API-only, 401 with GitLab PAT). CHANGELOG.md stays hand-rolled. Token CI var still provisioned (harmless).