refactor(turbo-tasks): Make State require OperationValue (#73876)
I started writing this PR by requiring `OperationValue` in `State`:
```diff
impl<T> State<T> {
- pub fn new(value: T) -> Self {
+ pub fn new(value: T) -> Self
+ where
+ T: OperationValue,
+ {
```
And then went through changing every compilation error that occurred as a result.
## Hacks
**There are some hacks in a number of places here where we incorrectly convert `ResolvedVc` to `OperationValue`.**
Unfortunately these have to exist because it's impractical to convert everything to `OperationValue`. `OperationValues` are harder to construct as they must be created directly from the return value of an unresolved function call.
## Why does `State<T>` need `T: OperationValue`?
`OperationVc` types require that `.connect()` is called before their value can be read.
As an internally-mutable type, `State` allows `Vc`s to be passed in ways that we cannot track. `.connect()` re-connects the `Vc` to the dependency graph so that strong resolution is possible.
Without this, you might end up with stale results when reading a `Vc` inside of `State`, which can be very hard to debug.
Fundamentally, I think `State` is unsound, but this is a band-aid on it until we can migrate to a better solution (likely effect-style `Collectibles` for `VersionedContentMap`).
next.js
afddbe7a - refactor(turbo-tasks): Make State require OperationValue (#73876)
