FR: restrict to `.ts` / `.css` files

[Chris Grieser]

I was pleased to see that this tool can also be used with themes!

So, I noticed that the download takes quite a bit of time, especially since it downloads the full repos, which also include the high-res promo screenshots from the themes, or demo-videos from the docs from plugins.

Since the purpose of this tool is primarily to inspect code and not screenshots, how about only downloading .ts and .css (or .scss)? this would immensely speed up the download, and also save bandwidth & file space.

There could be an option to still download the full repos if so wished by the user