docs: change pages to app router links (#71782)
## Description
Some links navigate pages docs.
Then update app router ones.
### Improving Documentation
- [x] Run `pnpm prettier-fix` to fix formatting issues before opening
the PR.
- [x] Read the Docs Contribution Guide to ensure your contribution
follows the docs guidelines:
https://nextjs.org/docs/community/contribution-guide
Co-authored-by: JJ Kasper <jj@jjsweb.site>
