Fix recent features & Add markdown and PDF support

[CookieSource]

This is a fairly large PR.

I’ve upgraded Starlight to the latest version and applied all required changes. Alongside this, the workflow has been updated to include fixes for features we’ve added recently.

This PR also introduces three new features:

1. An older PR that now functions correctly due to the updated workflow.
2. All pages are now copied as Markdown files, allowing users to append .md to a URL to view the Markdown version of any page.
3. Support for generating a PDF version of the documentation. The generated PDF is currently copied to the root directory and can be accessed at:
   https://aerynos.dev/aerynos.pdf

Deployment

A deployed test version can be viewed here:

• https://github.com/CookieSource/dotdev/deployments/github-pages
• https://aeryn.cookiesource.dev/

[NomadicCore]

Pulled and worked locally for me with the exception of pdf and .md links but as discussed on Zulip, this only happens when the site is built.

I can see it's working on your copy site.

[CookieSource]

I checked and it works on the main site as well I pulled down the test website.