dillon1000/react

[Fizz] Add resumeAndPrerender to Static Rendering (#30950)

This is only in the same experimental exports as `resume`. Useful with
Postpone/Halt.

We already have `prerender()` to create a partial tree with postponed
state. We also have `resume()` to dynamically resume such a tree.

This lets you do a new prerender by resuming an already existing
postponed state. Basically creating a chain of preludes. The next
prelude would include the scripts to patch up the document.

This mostly just works since both prerender and resume are already
implemented using the same code so we just enable both at the root. I'm
sure we'll find some edge cases since this wasn't considered when it was
first written but so far I've only found an unrelated existing bug with
`keyPath` fixed here.