Co-authored-by: artimath <ryanjhunter@gmail.com>

* Add sections to llms.txt

* Also add sitemap footer

* Revamp useOptimistic docs

* Updates from review

* Edit down a bit

* Updates from feedback

* Updates from feedback

* Updates from feedback

* fml, forgot startTransition again

* rm "prop"

* feedback from @stephan-noel

* feedback from @stephan-noel

* update note

Removed an extraneous "a" from the text

* More claude stuff

* more stuff from uee edit

* revert

This commit fixes the wording of __Rendering__ explanation paragraph
in the "components and hooks must be pure" page, according to the suggestion
so that it's easier to understand without any confusion around effects relation.