bug(MatInputTestHarness): setValue does not trigger "change" event

### 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

According to the documentation, the MatInput component emits a "change" event when the value changes. However, the test harness does not emit this event after "setValue()". See the stackblitz.

I have tried using focus() to focus the component before setting the value, then blur() to remove focus, which is what triggers "change" in the application, and there is still no "change" event.

### Reproduction

StackBlitz link: https://stackblitz.com/edit/phfedq5f?file=src%2Fexample%2Finput-harness-example.html
Steps to reproduce:
1. modified example test from https://material.angular.io/components/input/examples should run automatically
2. two tests fail because the event spy is not called

### Expected Behavior

You should be able to trigger the expected event with the test harness.

### Actual Behavior

Expected code associated with (change) to run.

### Environment

- Angular: 19
- CDK/Material: 19
- Browser(s): chrome
- Operating System (e.g. Windows, macOS, Ubuntu): Windows, macOs

Inizia con il comportamento di MatInputTestHarness descritto nell’issue ed esegui la riproduzione collegata di StackBlitz, basata sull’esempio di input Material modificato. Verifica gli spy degli eventi che falliscono attorno a setValue(), inclusi i tentativi di focus e blur. Il lavoro è completato quando viene eseguito il change handler previsto ed entrambi i test di riproduzione passano.

Scritto dal modello di indicizzazione a partire dal testo della issue.