Add a `color_from_index` randomized color palette generator

[alice-i-cecile]

          Since this method generates a nice sequence of colors based on the `u32` representation of an `Entity`, maybe we could offer a more general `pub fn color_from_index(index: u32) -> Oklcha`? Feels like a pretty handy function for debugging purposes, and might be nice for end users to have access to a color palette that can be programmatically accessed.

Originally posted by @bushrat011899 in #12163 (comment)