Allow toggling the grid of a ui.scene

[falkoschindler]

As @WolfgangFahl suggested in #1246, it would be nice to support toggling the visibility of the ground plane and/or the grid of a UI scene. Once we are at it, we might as well add optional coordinate axes like Wolfgang did in #1251.

[WolfgangFahl]

any progress?

[falkoschindler]

Not yet. So far this feature request hasn't seen any upvotes (apart from the two of us), let alone contributions.

Anyway, we could certainly introduce a method like set_grid_visibility. But playing around with this approach I noticed that there's also the ground plane which should be toggled as well - or shouldn't it? Sometimes you might want to hide both, sometimes only the grid. So we'd need even more methods for showing/hiding the grid, the ground plane, and maybe a coordinate axes indicator in the future. This makes the API less trivial.

[WolfgangFahl]

the solution in nicegui_widgets works by now see e.g. nicescad.bitplan.com