RTC: "Quick Edit" should be RTC-aware #79640

The "Quick Edit" button on the Post page can be used to edit a post title and other post meta (categories, tags, etc) by the same user holding the lock on a post. With RTC disabled, it's possible to have one title in one tab and a different title from a quick edit (from the same user):

This same behavior is possible with RTC enabled. This can be confusing for users who expect the "Quick Edit" buttons to be RTC-aware and update the editor contents in real-time. I wouldn't call this an "RTC bug" by itself, but it is behavior that feels broken in a modern editor. I think a good solution would be either to:

1. Allow "Quick Edit" fields like post title and taxonomy selections to connect to the RTC server and sync changes, or

2. Disable "Quick Edit" entirely when a user is editing a post. This is already the case if user B attempts a change while user A has a lock:

   quick-edit-blocked-other-user.mov

   The difference for RTC would be to also block the lock-holder from making "Quick Edit" changes while a post is actively being edited in a session. Full RTC support would be preferable, but this would prevent legacy behavior from confusing users in the meantime.