Support MCUs with built-in temperature sensors

Microcontrollers like the RP2040 and [ESP32-S2/S3, ESP32-C2/C3 ](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/api-reference/peripherals/temp_sensor.html) contain built-in temperature sensors. These are not ambient temperature sensors, they measure the temperature of the chip itself.

This temperature returned by these sensors is not very accurate (low resolution and generally higher than ambient temperature) but would serve as a quick way to get temperature data into IO without the use of external parts.

cc @lorennorman - This will likely need to be part of WipperSnapper_Components and WipperSnapper_Boards, too. Since it's _technically_ an ADC measurement, we could denote it as an analog pin component. Only certain microcontrollers have a sensor like this, we may want to figure out how to add this (possibly as a new value) to the `board.json` too.

References:
* https://github.com/espressif/esp-idf/tree/master/examples/peripherals/temp_sensor
* https://arduino-pico.readthedocs.io/en/latest/analog.html#float-analogreadtemp

Start by reviewing the WipperSnapper_Components and WipperSnapper_Boards areas, especially how board.json represents MCU capabilities. Compare the ESP-IDF temperature-sensor example with the Arduino-Pico analogReadTemp reference, then determine how supported built-in sensors should be exposed and how completion can be tested across the listed boards.

Written by the indexing model from the issue text.