[core] [lua] Actually enforce "must zone" and not just /logout

[WinterSolstice8]

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What does this pull request do?

Retail forces you to actually change zones instead of /logout. This PR makes it so you must do that as well.

Apparently also removes some edge case jank with pets too due to a misused variable

Steps to test these changes

Try a repeatable like Gourmet (see below) (uses mission/quest helper)

2026-03-31.15-07-30.webm

or Ranpi-Monpi's "A Crisis in the Making" (uses player:needToZone)