Followup to #11994

* Clean up Temperature PID
* Improve EEPROM read/write/validate
* Group `SINGLENOZZLE` saved settings
* Group planner saved settings
* Group filament change saved settings
* Group skew saved settings
* Group `FWRETRACT` saved settings

Addressing #12048

Co-Authored-By: timoxd7 <timoxd7@users.noreply.github.com>

Previously, it was not possible for the TYPE argument to ultralcd menu macros to itself be a #defined value. This made it difficult to create variables to set many related menu items to a common precision that could be easily changed.

Also added details to the README to make sure the Ender-2 status is properly documented.

* Allow override of soft SPI pins in `pins_*.h`
* Add default case to avoid compiler warning.
* Additional pin definitions for Archim 2.
* Einsy Retro has same timings as Einsy Rambo.

- Makefiles require tabs (not spaces) before shell commands.
- Other indentation can either be space or tabs.

…and change a multi-use "back" menu item.

* Don't react to s2g on TMC2660. False positives
* Init with sensorless probing as well

With default config and `EEPROM_SETTINGS`, saves over 200 bytes of PROGMEM.

Fix #12015

Fix #12004

CNC GCode dialect compatibility improvements

* Support new TMC library and 32-bit Archim board

- Added IS_MCU flag
  - When IS_MCU flag is 1, AVR compiler will be used
  - When IS_MCU flag is 0, ARM compiler will be used
- Added support for new TMC library
- Added support for a 32-bit Archim board, which could probably be used as a basis for other 32-bit boards.

[2.0.x] Add support for USB thumbdrives/flashdrives