* Encapsulate common LCD code in a singleton
* Depend more UBL code on UBL_DEVEL_DEBUGGING
  - Since most users don't need the debugging on at all times, this helps reduce the default build size for UBL by over 2K, a little closer to fitting on 128K boards.

* Followup to LCD_TIMEOUT_TO_STATUS=0
* Make continuous purge screen fit 20x4
* Unify purge message modes
* Preserve last-set pause header mode

Better encapsulation and considerably reduce stepper jitter

Co-Authored-By: ejtagle <ejtagle@hotmail.com>

Fix #8805

Addressing #7707