Improve / fix FTDI EVE Touch UI (#17338)

- Fix timeout and debugging string
- Fix check for whether `LCD_TIMEOUT_TO_STATUS` is valid
- Fix incorrect debugging message
- Make capitalization of callbacks consistent.
- Allow Touch UI to use hardware SPI on Einsy boards
- Move print stats to About Printer page.
- More generic about screen with GPL license.
- Add missing handler for power loss event
- Less code duplication on status screen and main/advanced menu; more legible
- Reorganize advanced and main menu to add more features
- Hide home Z button when using Z_SAFE_HOMING
- Fix compilation errors when certain features enabled
- Fix missing labels in UI
- Improve color scheme
- Add new preheat menus
- Fix incorrect rendering of Marlin logo on boot
- Add Level X Axis and Auto calibrate buttons

Marlin/src/lcd/extui_dgus_lcd.cpp

@@ -123,7 +123,7 @@ namespace ExtUI {
   }
 
   #if ENABLED(POWER_LOSS_RECOVERY)
-    void OnPowerLossResume() {
+    void onPowerLossResume() {
       // Called on resume from power-loss
       ScreenHandler.GotoScreen(DGUSLCD_SCREEN_POWER_LOSS);
     }
@@ -131,9 +131,9 @@ namespace ExtUI {
 
 
   #if HAS_PID_HEATING
-    void OnPidTuning(const result_t rst) {
+    void onPidTuning(const result_t rst) {
       // Called for temperature PID tuning result
-      SERIAL_ECHOLNPAIR("OnPidTuning:",rst);
+      SERIAL_ECHOLNPAIR("onPidTuning:",rst);
       switch(rst) {
         case PID_BAD_EXTRUDER_NUM:
           ScreenHandler.setstatusmessagePGM(PSTR(STR_PID_BAD_EXTRUDER_NUM));