Missing constraint error in instantiation expression for a nested class

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### 🔎 Search Terms

instantiation expression caching class expression declaration type arguments type parameter

### 🕗 Version & Regression Information

- This changed in PR: https://github.com/microsoft/TypeScript/pull/59931 , cc @weswigham

### ⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.9.0-dev.20250701#code/MYGwhgzhAECCA8AVaBeaA7ArgWwEYFMAnAPmgG8AoaaANzBE3wEIAuaRAbiumAAsBLEABNW0AJLoIAFzDpg+RAE8ADvnhSV+APYAzOADoAQvASJi5jtAD0V6FIEwIvLZmHQihLYQrdpYKfzA0IaoPOBQwUjuAB5S+OhCMLChsKSU1NTKYITxUqKc3AC+XIUUQA

### 💻 Code

```ts
class A {
value!: T;
child!: InstanceType>>; // this should error

static B = class B {
parent!: T;
};
}
```

### 🙁 Actual behavior

It doesn't error

### 🙂 Expected behavior

it should error with:
```
Type 'A' does not satisfy the constraint 'A'.
Type 'T' is not assignable to type 'number'.(2344)
```

like it did in 5.6: [TS playground](https://www.typescriptlang.org/play/?ts=5.6.3#code/MYGwhgzhAECCA8AVaBeaA7ArgWwEYFMAnAPmgG8AoaaANzBE3wEIAuaRAbiumAAsBLEABNW0AJLoIAFzDpg+RAE8ADvnhSV+APYAzOADoAQvASJi5jtAD0V6FIEwIvLZmHQihLYQrdpYKfzA0IaoPOBQwUjuAB5S+OhCMLChsKSU1NTKYITxUqKc3AC+XIUUQA)

### Additional information about the issue

The problem here is that the situation is a little bit circular and variances worker gets hits in reentrant manner. The nested call returns `emptyArray` that is a signal for `structuredTypeRelatedToWorker` to return `Ternary.Unknown`.

So `checkTypeArguments` called by `getInstantiatedSignatures` doesn't report an error. In the old version of the code, this would be re-called after the variance worker would completely exit and the error would be raised.

I see 2 ways to solve this:
- ignore the introduced caching based `inVarianceComputation` to avoid spoiling this
- defer `checkTypeArguments` in `getInstantiatedSignatures` (well, call it with `/*reportErrors*/ false` and defer anoher call with `/*reportErrors*/ true`)

Beginne mit dem verknüpften TypeScript Playground-Repro und verfolge getInstantiatedSignatures durch checkTypeArguments, structuredTypeRelatedToWorker und den inVarianceComputation-Pfad. Vergleiche das Verhalten mit dem 5.6 Playground-Link und bestimme, wie die verzögerte oder nicht zwischengespeicherte Prüfung den Constraint-Fehler melden sollte. Als erledigt gilt die Aufgabe, wenn das aktuelle Repro die Diagnose 2344 erzeugt, ohne verwandtes Type-Checking-Verhalten zu beeinträchtigen.

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