Feature Request: Custom inspector properties

[MatthiasJ1]

The measure tools are really neat, thanks! It would be great if we could specify custom properties to be displayed when inspecting an object. This could be done by registering a callback that would be called when a face is selected and would return a dict of additional properties to display. For completeness, the callback could also take the original properties ocp_vscode already defined in case it needs to be modified. An example use-case would be displaying face overhang angles for FDM printing.