Add support for catppuccin-whiskers

Catppuccin has a tool called [whiskers](https://github.com/catppuccin/whiskers) which is used to generate the color scheme files for different programs. It accepts color overrides in the form of JSON, and I made a JSON file that works with it in order to make a Carburetor scheme for Zed. Would you like a PR with that file and documentation on how to use it?