Proposal: Use tinted-theming builder to generate the colorschemes

[bezhermoso]

👋 Hi! Thank you for this plugin, I use it extensively.

I notice that there are PRs to add missing themes every now and again. May I propose a way in which that aspect of maintaining this repo could be made easier?

The tinted-theming org offers tools for generating theming artifacts for any tool, which I think might be of interest. Key aspects in my opinion:

• This repo can simply specify templates to replace most of tools/build.zsh
• The tinted-theming org actively maintains its schemes directory. The one this repo currently use is no longer maintained. It's been archived, thus missing themes and existing ones are out-of-date.)
• There exist a Github Action that will automate the generation to adopt to new schemes, as well as apply any changes.
• Integrate with the tool called tinty, which can coordinate the application of base16/base24 schemes system-wide.

I've been using an "adapter" for a while now that I just published to Github to hook these two systems together and it's been serving me well. Here is a POC fork that implements this proposal: https://github.com/RRethy/base16-nvim/compare/master...bezhermoso:tinted?body=&expand=1

I think adopting this system into the plugin itself could make some of the maintenance related to scheme additions/updates trivial going forward.

(Disclosure: I contribute to the tinted-theming org)