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

Beginne mit dem im Issue beschriebenen Verhalten von MatInputTestHarness und führe die verlinkte StackBlitz-Reproduktion basierend auf dem geänderten Material-Input-Beispiel aus. Überprüfe die fehlschlagenden Event-Spies um setValue(), einschließlich des Fokus- und des Blur-Versuchs. Fertig ist die Aufgabe, wenn der erwartete Change-Handler ausgeführt wird und beide Reproduktionstests bestehen.

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