Mostly from the L6470-oriented PR

* Make ExtUI respect MAXTEMP limits
  - Temperatures are now clamped by MAXTEMP limits rather than arbitrary values.
* Speed up USB init, add status
  - Speed up USB initialization
  - Show status message if init failed
* Enable status messages for EXTENSIBLE_UI
* Adjust max limit to MAX_TEMP - 15
* Misc. tweaks to formatting, const, etc.

* Make CardReader a static class
* Make CardReader flags into bitfields

* 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.

* Apply #pragma once in headers
* Adjust some thermistors formatting
* Misc cleanup and formatting

- A pullup on the INT pin is required when the pin is level-active

- Remove `print_job_timer.stop()` from `disable_all_heaters`
- Call `print_job_timer.stop()` for relevant `disable_all_heaters()`.
- Split up `kill()` for watchdog interrupt safety

- Fix an error in the return value of `sd_mmc_spi_read_capacity` which was causing the host OS to read beyond the last sector in the card.
- Clean up the USB flashdrive code and add better debugging.

Co-Authored-By: akunt

Better encapsulation and considerably reduce stepper jitter

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

Fix #10330