Cut a release

If this release includes a schema/data migration that is not already expand-safe and tested, finish it via ship-a-migration first — do not discover expand/contract mid-promote.

1. Readiness — assessing-release-readiness: scope, gates, risk surface, rollback plan → GO / GO-WITH-CONDITIONS / NO-GO.
2. Changelog — run the changelog command to draft release notes from merged work; apply copy-voice.
3. Promote — follow multi-plane-deploy (runbook) for the deploy order; tag the release.
4. Verify post-deploy on the affected paths; keep the rollback ready.

Hand-off: readiness gates the release; changelog documents it; the deploy runbook executes it in the right order.