[Feature] customize/add new control options

[Novakasa]

Is your feature request related to a problem? Please describe.
Currently we have one control scheme that relies on right- and left click (and optional middle mouse click).
Especially right click + drag is quite difficult on laptop trackpads.

Describe the solution you'd like
A very simple option could be to make left- and right click swappable
Also touch screen aware controls would be great, but that seems to only be supported in godot 4. godot 3 only has mouse emulation using touch screen.

Describe alternatives you've considered
We could go back to the "control modes" "select" "draw" and "control", but that would reintroduce some complexity

Additional context
Inspired by #119 (comment)