Hide the new Phriction "Publish" operation behind the "Prototype" toggle
Summary: Ref T13077. This is currently a little too confusing to go out into the world, mostly because there's no way to edit documents without auto-publishing them. Keep it out of the spotlight for this release.
Test Plan: Viewed Phriction, saw publish operation marked as a prototype.
Maniphest Tasks: T13077
Differential Revision: https://secure.phabricator.com/D19627