🚸 Improve Tramming Wizard usability (#22672)

Marlin/src/lcd/extui/example/example.cpp

     void onPidTuning(const result_t rst) {
       // Called for temperature PID tuning result
       switch (rst) {
+        case PID_STARTED:          break;
         case PID_BAD_EXTRUDER_NUM: break;
         case PID_TEMP_TOO_HIGH:    break;
         case PID_TUNING_TIMEOUT:   break;

Marlin/src/lcd/menu/menu_tramming.cpp

 //#define DEBUG_OUT 1
 #include "../../core/debug_out.h"
 
-float z_measured[G35_PROBE_COUNT] = { 0 };
+static float z_measured[G35_PROBE_COUNT];
+static bool z_isvalid[G35_PROBE_COUNT];
 static uint8_t tram_index = 0;
+static int8_t reference_index; // = 0
 
 #if HAS_LEVELING
   #include "../../feature/bedlevel/bedlevel.h"
   do_blocking_move_to_z(TERN(BLTOUCH, Z_CLEARANCE_DEPLOY_PROBE, Z_CLEARANCE_BETWEEN_PROBES));
   // Stow after each point with BLTouch "HIGH SPEED" mode for push-pin safety
   const float z_probed_height = probe.probe_at_point(tramming_points[tram_index], TERN(BLTOUCH_HS_MODE, PROBE_PT_STOW, PROBE_PT_RAISE), 0, true);
-  DEBUG_ECHOLNPAIR("probe_single_point: ", z_probed_height, "mm");
   z_measured[tram_index] = z_probed_height;
+  if (reference_index < 0) reference_index = tram_index;
   move_to_tramming_wait_pos();
 
-  return !isnan(z_probed_height);
+  DEBUG_ECHOLNPAIR("probe_single_point(", tram_index, ") = ", z_probed_height, "mm");
+  return (z_isvalid[tram_index] = !isnan(z_probed_height));
 }
 
-static void _menu_single_probe(const uint8_t point) {
-  tram_index = point;
-  DEBUG_ECHOLNPAIR("Screen: single probe screen Arg:", point);
+static void _menu_single_probe() {
+  DEBUG_ECHOLNPAIR("Screen: single probe screen Arg:", tram_index);
   START_MENU();
   STATIC_ITEM(MSG_BED_TRAMMING, SS_LEFT);
-  STATIC_ITEM(MSG_LAST_VALUE_SP, SS_LEFT, ftostr42_52(z_measured[0] - z_measured[point])); // Print diff
+  STATIC_ITEM(MSG_LAST_VALUE_SP, SS_LEFT, z_isvalid[tram_index] ? ftostr42_52(z_measured[reference_index] - z_measured[tram_index]) : "---");
   ACTION_ITEM(MSG_UBL_BC_INSERT2, []{ if (probe_single_point()) ui.refresh(); });
-  ACTION_ITEM(MSG_BUTTON_DONE, []{ ui.goto_previous_screen(); }); // Back
+  ACTION_ITEM(MSG_BUTTON_DONE, []{ ui.goto_previous_screen(); });
   END_MENU();
 }
 
 static void tramming_wizard_menu() {
-  DEBUG_ECHOLNPAIR("Screen: tramming_wizard_menu");
   START_MENU();
   STATIC_ITEM(MSG_SELECT_ORIGIN);
 
   // Draw a menu item for each tramming point
-  LOOP_L_N(i, G35_PROBE_COUNT)
-    SUBMENU_N_P(i, (char*)pgm_read_ptr(&tramming_point_name[i]), []{ _menu_single_probe(MenuItemBase::itemIndex); });
+  for (tram_index = 0; tram_index < G35_PROBE_COUNT; tram_index++)
+    SUBMENU_P((char*)pgm_read_ptr(&tramming_point_name[tram_index]), _menu_single_probe);
 
   ACTION_ITEM(MSG_BUTTON_DONE, []{
     probe.stow(); // Stow before exiting Tramming Wizard
 // Init the wizard and enter the submenu
 void goto_tramming_wizard() {
   DEBUG_ECHOLNPAIR("Screen: goto_tramming_wizard", 1);
-  tram_index = 0;
   ui.defer_status_screen();
 
+  // Initialize measured point flags
+  ZERO(z_isvalid);
+  reference_index = -1;
+
   // Inject G28, wait for homing to complete,
   set_all_unhomed();
   queue.inject_P(TERN(CAN_SET_LEVELING_AFTER_G28, PSTR("G28L0"), G28_STR));

buildroot/tests/DUE

         TEMP_SENSOR_CHAMBER 3 TEMP_CHAMBER_PIN 6 HEATER_CHAMBER_PIN 45
 opt_enable S_CURVE_ACCELERATION EEPROM_SETTINGS GCODE_MACROS \
            FIX_MOUNTED_PROBE Z_SAFE_HOMING CODEPENDENT_XY_HOMING \
-           ASSISTED_TRAMMING ASSISTED_TRAMMING_WIZARD REPORT_TRAMMING_MM ASSISTED_TRAMMING_WAIT_POSITION \
+           ASSISTED_TRAMMING REPORT_TRAMMING_MM ASSISTED_TRAMMING_WAIT_POSITION \
            EEPROM_SETTINGS SDSUPPORT BINARY_FILE_TRANSFER \
            BLINKM PCA9533 PCA9632 RGB_LED RGB_LED_R_PIN RGB_LED_G_PIN RGB_LED_B_PIN LED_CONTROL_MENU \
            NEOPIXEL_LED NEOPIXEL_PIN CASE_LIGHT_ENABLE CASE_LIGHT_USE_NEOPIXEL CASE_LIGHT_USE_RGB_LED CASE_LIGHT_MENU \

buildroot/tests/LPC1768

 opt_enable REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER ADAPTIVE_FAN_SLOWING NO_FAN_SLOWING_IN_PID_TUNING \
            FILAMENT_WIDTH_SENSOR FILAMENT_LCD_DISPLAY PID_EXTRUSION_SCALING SOUND_MENU_ITEM \
            NOZZLE_AS_PROBE AUTO_BED_LEVELING_BILINEAR PREHEAT_BEFORE_LEVELING G29_RETRY_AND_RECOVER Z_MIN_PROBE_REPEATABILITY_TEST DEBUG_LEVELING_FEATURE \
+           ASSISTED_TRAMMING ASSISTED_TRAMMING_WIZARD REPORT_TRAMMING_MM ASSISTED_TRAMMING_WAIT_POSITION \
            BABYSTEPPING BABYSTEP_XY BABYSTEP_ZPROBE_OFFSET BABYSTEP_ZPROBE_GFX_OVERLAY \
            PRINTCOUNTER NOZZLE_PARK_FEATURE NOZZLE_CLEAN_FEATURE SLOW_PWM_HEATERS PIDTEMPBED EEPROM_SETTINGS INCH_MODE_SUPPORT TEMPERATURE_UNITS_SUPPORT \
            Z_SAFE_HOMING ADVANCED_PAUSE_FEATURE PARK_HEAD_ON_PAUSE \