bug(popups): Material popups shown from native HTML dialog don't register mouse events.

### 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

Mouse events not registering on multiple material components inside native Dialog.

Originally they appeared behind the dialog due to being created outside of #top-layer.
https://github.com/angular/components/issues/25799

Now they mostly just don't work. They appear in-front of dialog... but mouse events (click/hover) don't register.
https://stackblitz.com/edit/stackblitz-starters-wmwfsj8g?file=src%2Fmain.ts

### Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-wmwfsj8g?file=src%2Fmain.ts
Steps to reproduce:
1. click button to open a native dialog
2. click any of the material components

### Expected Behavior

The MatMenu and DatePicker should work as expected.

### Actual Behavior

Ignores mouse events.

### Environment

- Angular: 21.1.3
- CDK/Material: 21.1.3
- Browser(s): Chrome
- Operating System (e.g. Windows, macOS, Ubuntu): macOS

src/main.ts にあるリンク先の StackBlitz の再現コードから始め、Chrome で動作を確認します。ネイティブダイアログを開き、続いて MatMenu と DatePicker を試します。これらの Material ポップアップがネイティブダイアログの top layer に対してどのように配置されるかを追跡し、クリックイベントと hover イベントがコンポーネントに届くことを確認します。ダイアログを開いた状態で、両方のコンポーネントがマウスイベントに反応すれば完了です。

索引モデルが issue の本文から書いたものです。