Add a chromatic mask shader

My recent feature requests will be mainly for the aid of working with large complex scenes which are used as a basis for concept art work in ProCreate.

A very important feature I would like to see is a a chromatic Mask where each layer gets a random color.

Once layer grouping arrives I guess one could decided whether the group gets the same color or not.

As a work around I duplicate the scene and assign colors manually in unlit mode. Very tedious and high chance of redundancy.