Turbopack: Remove old `Vc::try_resolve_*` methods in favor of the `ResolvedVc` alternatives (#89696)
These `try_resolve_*` methods predate the introduction of the `ResolvedVc` type.
`ResolvedVc` has efficient synchronous `try_downcast`/`try_sidecast` functions, and there are only a few callsites that need to do this, so it makes more sense to split the resolution and the casting into to separate calls.