Custom Buttons Fixate

[amp-bjorn]

Ability to add custom buttons for jig calibrations or capturing data that currently cannot be captured in fixate.

[amp-bjorn]

user_info(f"custom buttons")
result = _user_req_choices("", target=_user_choices, choices=("-", "SAVE", "+"))

[Jasper-Harvey0]

Should be getting fixed in: #254