Consider moving the website into main rust-gpu repo

I just threw it in here as that was the quickest way to get the webpage up with github pages.

Docs/website in the main repo:

Pros:

• Docs stay close to the code, so it’s easier to keep them updated alongside changes.
• Contributors only need to work in one place, so adding or updating docs is straightforward.
• No need to manage multiple repos—everything lives together.
  Cons:
• The repo gets bigger, which can slow down cloning and pull requests for everyone.
• Mixing code and doc issues in one place can get messy, making it harder to focus on core development.

Using a separate repo for docs/website:

Pros:

• Keeps the main repo cleaner and code-focused, so it’s easier to navigate.
• Doc updates are simpler to track and review on their own, without touching the code.
• Main repo stays leaner and faster to work with.
  Cons:
• It’s tougher to keep docs in sync with code changes, as they’re in different places.
• Managing a separate repo adds overhead, like additional issue tracking and reviews.

This issue is a repository-organization proposal rather than a defined implementation task. Review the current website repository and the main rust-gpu repository, then decide where the website and documentation should live. Done means reaching and recording a clear decision, including any migration scope.