Change notes entered in the edit form are never submitted

[mliebischer]

Problem

The edit form (@@edit) offers a change-note field (schema-driven via the plone.versioning behavior), but a note entered there never shows up afterwards — neither in the @@history view's "Change note" column nor in the @history REST payload.

Steps to reproduce

1. Edit any versionable content via @@edit.
2. Fill in the change-note field and save.
3. Open @@history for that content.
4. The new versioning entry has an empty "Change note".

Analysis so far

• The History view is not the culprit: its "Change note" column renders the comments field from the @history endpoint, and entries that do have comments (e.g. created through Volto) display fine.
• changeNote is not handled anywhere in @plone/cmsui outside the History view, so the edit route most likely never includes the note in the PATCH request.
• Prior art: Volto's form sends changeNote along with the save request, and plone.restapi passes it to the versioning machinery.

Expected behavior

A change note entered in the edit form is submitted with the save request and appears as the comments of the resulting versioning entry in @history / the @@history view.

References

• [CMSUI] - History route #30 / Add History route (#30) #120 (History view, where the missing notes were noticed)
• Volto: packages/volto/src/components/manage/Form/Form.jsx (changeNote handling)