docs: combine and improve RSC docs (#13971)

* Start new RSC doc and add API examples

* Add Parcel and Vite examples

* Add a little comment

* Try to clarify route modules piece more

* delete the remaining old rsc docs

* llm cleanup

* Minor updates

* Update with PR feedback

* entry.client -> entry.browser

* Clarify that SSR is not required

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Co-authored-by: Matt Brophy <[email protected]>

Author: brookslybrand