Add Sofirn SC13 and catch up to TK

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Add the new Sofirn SC13 model

Base Anduril changes:

• Added code for controlling the charging indicator LED through the MCU as part of the WDT logic (added but commented-out code for blinking the LED while charging - handy for red/green colorblind folks but not desired by Sofirn)
• Within Version Check, created a new BUZZ_SPEED setting so that we can slow down buzz pulses for really slow regulators (eg, SC13)