Request: Allow setting different default layout for regular window vs. full screen

[milnak]

Discussed in #4752

^{Originally posted by milnak January 5, 2025}
when window is in regular state, i'd like "single page", "non-continuous"
in full screen (Ctrl+L or Shift+Ctrl+L) I'd like "Facing" or "Book View".

I can't figure out how to do this, so if it doesn't exist, it would be nice to add.