Invalid bytes passed to HAL_SendError cause confusing unicode errors

[virtuald]

I think the error occurs when pybind11 is converting the string arguments for the error handler to utf-8. Since there's no guarantee that the error message is actually valid utf-8, probably should change the error handler to take bytes instead and have it do the conversion so it can catch the error.

Reference: https://www.chiefdelphi.com/t/unicodedecodeerror-calling-sparkmax-iterate-with-2025-robotpy/475775