Who is editing in this session, for repos whose commits must name a person (knowledgebases and wikis edited through a shared agent session). Use when the editor-police hook denies a commit, before the first commit to such a repo in a session, or when someone says a different person has taken over the keyboard. Asks once per session, records the answer, and puts that person on every commit as an Edited-by trailer so page stamps and changelogs name them.
