Allow returning a temporary reference inside an async function (#33761)

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## Summary

Fixes `await`-ing and returning temporary references in `async`
functions. These two operations invoke `.then()` under the hood if it is
available, which currently results in an "Cannot access then on the
server. You cannot dot into a temporary client reference..." error. This
can easily be reproduced by returning a temporary reference from a
server function.

Fixes #33534

## How did you test this change?
I added a test in a new test file. I wasn't sure where else to put it.
<img width="771" height="138" alt="image"
src="https://github.com/user-attachments/assets/09ffe6eb-271a-4842-a9fe-c68e17b3fb41"
/>

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DiffTrain build for [1d163962b21f9396d26930e31719bd8b10d9e107](https://github.com/facebook/react/commit/1d163962b21f9396d26930e31719bd8b10d9e107)