The admin signs in with the shared password, creates a Menu Set, drops photos
into it (shrunk in the browser first), reorders Pages by dragging or with
up/down buttons, previews the Draft exactly as customers would see it, and
publishes it over the previous set. Restore and delete close the loop. Mutations
need a session, a same-origin request and a CSRF token derived from the session;
a Draft's media is served only to a session holder.
