bug(MatAutoComplete): requiredSelection value racecon on panel close

### 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

Autocomplete using "requiredSelection" results in a racecon upon closing the panel

https://github.com/user-attachments/assets/5b211777-c457-47a1-8096-3894430e0d2d

### Reproduction

StackBlitz link: https://stackblitz.com/edit/q5xjs54i?file=src%2Fexample%2Fautocomplete-require-selection-example.ts
Steps to reproduce:
1. open panel
2. while panel is open click reset button

### Expected Behavior

Control value should be set after clicking "reset" button while the autocomplete panel is open

### Actual Behavior

Control has no value after clicking "reset" button while the autocomplete panel is open

### Environment

- Angular: 19.0.0
- CDK/Material: 19.0.0
- Browser(s):
- Operating System (e.g. Windows, macOS, Ubuntu):

Start with the linked StackBlitz reproduction in src/example/autocomplete-require-selection-example.ts, focusing on the reset button while the autocomplete panel is open. Trace the panel-close and reset sequence; done means the control retains its value after reset, matching the expected behavior.

索引モデルが issue の本文から書いたものです。