The version job ran `bunx changeset version` to consume .changeset/*.md
files and update CHANGELOG.md, but the publish job (which commits and
pushes) ran on a separate runner with a fresh checkout — discarding all
changelog changes. This caused CHANGELOG.md to stay stuck at 7.2.1
despite 9 subsequent releases.
Move changeset consumption into publish.ts so it runs on the same runner
that commits. Extract release notes from the updated changelog and pass
them to `gh release edit` so GitHub releases also get correct notes.