Customizable map colors

[Helium314]

With the switch to MapLibre, the map style can come from "anywhere", including a local json file. Light and Dark styles currently use SC-Provided json files, while Dark Contrast style makes use of the map style creator to create such a file. As you can see, the map Colors can be defined very easily, so a UI to customize colors would just need a list of colors, and a color picker.
Maybe an option to share the colors could also be included.

Further, users could also provide a json file instead, so much more than just colors could be customized.

Main problem currently: SCEE settings UI should be migrated to compose, and I don't want to do any work on settings before this is done.
Potential other problem: Colors is not guaranteed to be stable, so there is a chance that things break on a future upgrade.