Finish powermon/powerstress

[geeksville]

This is the final changes for the powermon/powerstress stuff. Sorry for the long list of CLs, but I have been merging from master for a while so hard to rebase/collapse the various non merge changes into a single CL.

There are three main changes:

• Implement the PowerStress class so that the python code can ask the unit under test (UUT) to transition through various modes while it measures the power consumed by the board. (This class is not used in normal operation)
• Have various places that are doing power changing things (turning on power rails, changing radio modes etc...) call hooks on the powermon singleton to indicate those operations are happening. Those hooks emit a structured string to the log file output. This class is tiny so I left it on by default.
• Add GpioTransformer/GpioPin classes which I will soon use for decreasing Heltec tracker power consumption (by managing the dedicated screen+gps power regulator more conservatively). Currently this class is only used for the power led (so that the led can be controlled by PowerStress - and then we eventually calibrate/detect from the python side that the bench power measurement is working).

Any feedback/comments would be appreciated! (sorry for the delay - I took an extra week off from programming but now back at it)

For #4136

[todd-herbert]

Nothing looked odd to me, but when I built and ran this for T-Beam V1.2 it crashes at boot.
(Update: same for DIY V1)

0x40152b0f: do_global_ctors at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:201
0x40152b0f: start_cpu0_default at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:449
0x40083aad: call_start_cpu0 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/port/cpu_start.c:687

Not sure if it's this PR or something unrelated from master. Will keep building stuff here and see if anything turns up.

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Update: Heltec Wireless Paper (ESP32-S3) also crashing on boot:

#0  0x42003848 in _ZN8PowerMon8setStateE26_meshtastic_PowerMon_StatePKc$constprop$944 at ??:?
  #1  0x42065345 in MonitoredLedPin::set(bool) at ??:?
  #2  0x420652e2 in GpioBinaryTransformer::update() at ??:?
  #3  0x42009b9a in global constructors keyed to 65535_0_BluetoothCommon_cpp_o$235855 at :?
  #4  0x42076096 in do_global_ctors at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:201
      (inlined by) start_cpu0_default at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/startup.c:449
  #5  0x4037744f in call_start_cpu0 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/port/cpu_start.c:687

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Update 2: master seems to still be running fine

[geeksville]

@todd-herbert your note prompted me to try it on a tbeam! You are correct. I'll take a look!

[geeksville]

thanks @todd-herbert - I think ready to go (again ;-) )

[todd-herbert]

Looks like you got it! All running as normal here 👍

[geeksville]

thanks @todd-herbert. Updated wrt master (and retested on tbeam and rak4631) and I think ready to merge. cool @thebentern? (I'm lazy and eager to not keep updating wrt master. heh)

[thebentern]

Sounds good. Merging :D