* docs: change configurations to make v2 the main docs
* move api routes to top level
* remove api prefix
* update opengraph images
* show v1 link
* add redirect to v1
- Add a new homepage to `book` project for the routing page
- Move all main doc pages to be under `/v2/learn` (and added redirects + fixed links across docs)
- Other: add admin components to resources dropdown + fixes to search on mobile.
Closes DX-955
Preview: https://docs-v2-git-docs-router-page-medusajs.vercel.app/v2
