feat: inject minified css in bundle

[arielweinberger]

Description

• removes the need to import styles.css manually
• empty styles.css included in the build for backwards compatibility
• uses tsup's injectStyles with postcss to bundle and minify the CSS, then inject it as a style tag
• currently uses my fork of tsup where I added support for async function in injectStyles (must-have for postcss), a PR from my fork to the main library will follow shortly
• remove material-ui, and use react-icons for icons (same icons as before)
• remove unused IncludedFilesPreview component
• updated docs

How to test this

Check out the preview deployment below.

• To test the changes of react-ui, head over to /presentation
• To test the changes of react-textarea, head over to /textarea

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
copilotkit-example-next-openai	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 13, 2024 1:03pm
docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 13, 2024 1:03pm

[mme]

As far as I can tell, this looks good.

Just some pointers:

• search the code for "@copilotkit/react-ui/styles.css" and the other css files, I'm pretty sure there are more occurences
• We should QA usage in different frameworks e.g. remix

[arielweinberger]

We should QA usage in different frameworks e.g. remix

I don't think there's anything that could be affected by frameworks:

        if (globalThis.hasOwnProperty("document")) {
          const style = document?.createElement("style");
          style.innerHTML = '${resultCSS}';
          document?.head.appendChild(style);
        }