[compiler] Allow assigning ref-accessing functions to objects if not mutated (#34026)

Allows assigning a ref-accessing function to an object so long as that
object is not subsequently transitively mutated. We should likely
rewrite the ref validation to use the new mutation/aliasing effects,
which would provide a more consistent behavior across instruction types
and require fewer special cases like this.

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[//]: # (BEGIN SAPLING FOOTER)
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* #34027
* __->__ #34026

DiffTrain build for [04a7a61918522734a083bff37843865d7815d466](https://github.com/facebook/react/commit/04a7a61918522734a083bff37843865d7815d466)