feat: reduce initial css load

[anh-ld]

What kind of changes does this PR include?

• Reduce initial CSS load from 10.5KB to 7.9KB by lazy loading @pagefind/default-ui/css/ui.css and its customized CSS.

Description

• I moved the @pagefind/default-ui/css/ui.css and the Search.astro's <style is:global> into styles/search.css and then lazy load the styles/search.css onIdle.

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[github-actions]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[chrismwilliams]

Thanks for opening this and for taking the time to do this.

I appreciate the savings, but I'm not sure if this will trip some people up with View Transitions, it would require testing to make sure it's compatible as I've had some issue's with it already and ended up removing it.

There's also caching with the styles being in a .js file, and with the possibility of people clicking search before the styles have been processed.

What I can do is put a link in the README to your request as a possible solution to reduce initial load.