Windows com port handling QOL/usability improvement

[timp3289]

On windows, opening a COM port above COM9 needs to use syntax \.\COM10 instead of just COM10 in the winapi CreateFileA()
Currently, specifying just COM10 will cause the port to fail to open.

Can/should we

• automatically correct this
• Put a more specific error message than "can't open COM port"
• Put a note somewhere in the GUI?

seeking feedback so I can implement an improvement to the current behaviour

[azonenberg]

Error reporting for transport issues is something I want to work on at some point.

But for this specific case, I think automatically correcting is straightforward to do. Maybe it would make more sense to implement on the xptools side than the transport side? Just make sure to check for the \.\ first, so you don't double-escape correctly formatted port names