Moved pages should redirect to new page locations

[JoshuaKGoldberg]

What version of Effect is running?

n/a

What steps can reproduce the bug?

1. Visit https://effect.website/docs/style/brands
2. Get a 500 internal server error from 404 pages not being handled well: 500: Internal Server Error on 404 pages #462

What is the expected behavior?

When a page resources moves, there should be some kind of indication on the old page that the resource is now located at a different page. 301 Permanent Redirect is one common way to do that.

What do you see instead?

Following a move of the page on type brands, Google still shows a featured snippet for the old page:

Additional information

https://developer.mozilla.org/en-US/docs/Web/HTTP/Redirections documents HTTP redirects.

https://developers.google.com/search/docs/crawling-indexing/site-move-with-url-changes has docs, in particular https://developers.google.com/search/docs/crawling-indexing/site-move-with-url-changes#create-a-mapping-of-old-to-new-urls for more redirect strategies.