bug(form-field): Updating input value via `effect`+`FormControl` doesn't trigger label position calculation

### Is this a regression?

- [ ] Yes, this behavior used to work in the previous version

### The previous version in which this bug was not present was

_No response_

### Description

When updating a `FormControl` value inside a signal `effect`, the `MatFormField` floating label does not reposition under `OnPush` change detection unless `ChangeDetectorRef.markForCheck()` is called manually.

### Reproduction

StackBlitz link: https://stackblitz.com/edit/ujogbvgu?file=src%2Fexample%2Fform-field-overview-example.ts
Steps to reproduce:
1. Update input via `FormControl` + `effect`
2. Observe that label position does not update unless `ChangeDetectorRef.markForCheck()` is invoked explicitly.

### Expected Behavior

Using `signal`s and `effect`s, I expected not to have to call `ChangeDetectorRef.markForCheck()` for the label to float.

### Actual Behavior

The label did not float when the control's value was set.

### Environment

- Angular: 20.2.x
- CDK/Material: 20.2.x
- Browser(s): Chrome
- Operating System (e.g. Windows, macOS, Ubuntu): Windows

Commencez par la reproduction dans src/example/form-field-overview-example.ts et suivez les étapes de StackBlitz en utilisant FormControl et effect avec la détection des changements OnPush. Suivez la mise à jour de la position du label de MatFormField et vérifiez que le label flotte après la modification de la valeur du contrôle, sans appeler manuellement ChangeDetectorRef.markForCheck().

Rédigé par le modèle d'indexation à partir du texte de l'issue.