Enforce sensor range for temperature target (#18465)

* Mitigate stepper timeout

* Add CHAMBER PWM code

* Structured thermistor tables

* Fix reversed sensor ranges

* Prevent temps outside sensor range

Marlin/src/gcode/gcode.cpp

@@ -59,7 +59,10 @@ GcodeSuite gcode;
 
 #include "../MarlinCore.h" // for idle()
 
-millis_t GcodeSuite::previous_move_ms;
+// Inactivity shutdown
+millis_t GcodeSuite::previous_move_ms = 0,
+         GcodeSuite::max_inactive_time = 0,
+         GcodeSuite::stepper_inactive_time = SEC_TO_MS(DEFAULT_STEPPER_DEACTIVE_TIME);
 
 // Relative motion mode for each logical axis
 static constexpr xyze_bool_t ar_init = AXIS_RELATIVE_MODES;