MHP30: Shutdown settings (#1307)

* Reduce PPS max to 20V to avoid instability

Some PSU's cant actually run at 21V

* Creating a rough draft of a "pre start check" concept

* Newer alpine

* Cleaning up MHP detection

* Cleanup comments

* PID: Run prestart based on ADC IRQ rather than times

* MHP30: Far better startup for detecting tip gain

* Newer alpine for github CI

* Bugfix: Exit on movement

* Feature: Shutdown timeout for MHP30

source/Core/Threads/PIDThread.cpp

@@ -17,7 +17,7 @@
 static TickType_t powerPulseWaitUnit      = 25 * TICKS_100MS;      // 2.5 s
 static TickType_t powerPulseDurationUnit  = (5 * TICKS_100MS) / 2; // 250 ms
 TaskHandle_t      pidTaskNotification     = NULL;
-uint32_t          currentTempTargetDegC   = 0; // Current temperature target in C
+volatile uint32_t          currentTempTargetDegC   = 0; // Current temperature target in C
 int32_t           powerSupplyWattageLimit = 0;
 bool              heaterThermalRunaway    = false;