Low battery warning

[pepijndevos]

The badge runs on a LiPo cell that supposedly has an under-voltage protection, which most likely kicks in at a lower voltage than what is healthy for the battery. It is generally not recommended to discharge a LiPo below 3V.

It would be great if the launcher could give a warning when the battery is low.

But ahem some users might be running apps for a long time that draw power. An additional feature would be that the RP2040 resets the badge so that the launcher could display the warning.

Another thing could be to put a snippet in the docs, like the one to read the home button and reset, to check the battery voltage.

[pepijndevos]

Turns out the badge just stops working at 3.3V so this is pretty low priority.