Adding a Transformation tool for Joint origin placement. Ask idea - how to

[drfenixion]

I tried to do fast fix for add transform tool but i dont have experience with FreeCAD dev and need your opinion.

I tried to use App::GeometryPython instead of App::FeaturePython in joint_proxy it looks same but with geometric features. Also added placement property.
That appear transform tool in menu, but tool does not work (without any errors, just does not appear in 3d space).
Also tried various extensions for App::GeometryPython. They also does not give working transform tool.

I tried other objects like App:Part that give working transform tool but it is not right way because they have not proxy property and thus not compatible with current code.

@galou , any idea that i should to use in code for getting working transform tool and also have proxy for compatible?

My current idea is adding transform tool with something like App::GeometryPython (instead of App::FeaturePython in joint_proxy.py) and when it will change placement do sync with origin (for compatible). Also it may be need to fix ciclic update placement<->origin (if will).