🚸 Fix duplicate temperature report (#26952)

Marlin/src/MarlinCore.cpp

@@ -266,7 +266,7 @@ PGMSTR(M112_KILL_STR, "M112 Shutdown");
 MarlinState marlin_state = MF_INITIALIZING;
 
 // For M109 and M190, this flag may be cleared (by M108) to exit the wait loop
-bool wait_for_heatup = true;
+bool wait_for_heatup = false;
 
 // For M0/M1, this flag may be cleared (by M108) to exit the wait-for-user loop
 #if HAS_RESUME_CONTINUE

Marlin/src/module/temperature.cpp

@@ -4419,6 +4419,7 @@ void Temperature::isr() {
   #if ENABLED(AUTO_REPORT_TEMPERATURES)
     AutoReporter<Temperature::AutoReportTemp> Temperature::auto_reporter;
     void Temperature::AutoReportTemp::report() {
+      if (wait_for_heatup) return;
       print_heater_states(active_extruder OPTARG(HAS_TEMP_REDUNDANT, ENABLED(AUTO_REPORT_REDUNDANT)));
       SERIAL_EOL();
     }