Add fields to schema that provide for notes during the review / publish workflow

May need notes for each "persona" in the workflow, but TBD how many there will be.
E.g.,
Submitter(?)
Reviewer
Editor
Admin(?)

First clarify which workflow personas need notes and how many are supported, since the issue leaves both open. Then locate the schema entry point and review how the review/publish workflow represents Submitter, Reviewer, Editor, and Admin; the work is done when the agreed notes fields are represented for the required personas and the schema remains consistent.

Written by the indexing model from the issue text.