Feature request : Add parseHex() to serial library

It will be very useful when we want to pass hexadecimal values through the serial monitor. Could be easily implemented using sscanf with "%2" in the background over temporary buffer of next 2 valid hexadecimal ASCII characters

Locate the serial library and its existing value-parsing entry points first; no specific file or test is named in the issue. Determine the expected parseHex() input and output behavior from the current API, then add coverage for hexadecimal characters and invalid input so completion is verifiable.

Written by the indexing model from the issue text.