json: add json representation of schemes

[colemickens]

Hi,

From what I can tell, the iterm colorscheme xml files are the source of truth and the theme-settings files for each terminal is rendered from that.

My goal is to re-use iterm2-color-schemes in the nix-rice project so that NixOS users can choose an iterm2 color theme and have it automatically applied to all of their installed terminals.

However, I don't want to handle XML parsing in Nix, as that's far more involved than parsing a JSON or TOML file. However, I'm not immediately seeing a JSON or TOML representation that contains all of the information from the schemes file.

(For example, the json and tomls I've looked at clearly have a smaller subset of all of the values that I can see skimming through the scheme XML files)

So, my ask would be, would you support a "schemes-json" folder that is "rendered" like other terminals, but would contain all the names/values from the xml scheme. This would make the full scheme data available programmatically, in a more convenient manner.

[colemickens]

I think I have a few questions:

1. why is there ./themes and ./example/themes?
2. why are there some themes duplicated in nix, rather than using the kitty-themes?