bug: IonAlert hijacks 'insertLineBreak' when using `inputs`

### Prerequisites

- [x] I have read the [Contributing Guidelines](https://github.com/ionic-team/ionic-framework/blob/main/docs/CONTRIBUTING.md#creating-an-issue).
- [x] I agree to follow the [Code of Conduct](https://ionicframework.com/code-of-conduct).
- [x] I have searched for [existing issues](https://github.com/ionic-team/ionic-framework/issues) that already report this problem, without success.

### Ionic Framework Version

v8.x

### Current Behavior

- IonAlert has an option to add `inputs`.
- When adding checkbox inputs to the ion-alert, on any page in any location, any textarea or other input in which you want to input a linebreak is impossible.
- The ion-alert inputs seem to be hijacking the 'beforeinput' event or the e.inputType === 'insertLineBreak'.
- Having isOpen true or false has no effect.

### Expected Behavior

Linebreaks are possible when an IonAlert with custom inputs are present.

### Steps to Reproduce

### check the code reproduction

1. open or close ion-alert (does not matter)
2. open console and observe the log for the linebreak event
3. type text into the text area and hit enter key for a linebreak
4. toggle inputs for ion-alert from 5 checkboxes to an empty array
5. type text into the text area and hit enter key for a linebreak

### Code Reproduction URL

https://react-9q8cq9kr.stackblitz.io

### Ionic Info

### From my normal project (not the code reproduction repo)
Ionic:

Ionic CLI : 7.2.1 (C:\Users\mysecretusername\AppData\Roaming\nvm\v22.19.0\node_modules\@ionic\cli)
Ionic Framework : @ionic/react 8.7.6

Capacitor:

Capacitor CLI : 7.4.3
@capacitor/android : 7.4.3
@capacitor/core : 7.4.3
@capacitor/ios : 7.4.3

Utility:

cordova-res : not installed globally
native-run : 2.0.1

System:

NodeJS : v22.19.0 (C:\Program Files\nodejs\node.exe)
npm : 10.9.3
OS : Windows 10

### Additional Information

_No response_

Start with the linked StackBlitz reproduction and inspect IonAlert's handling of checkbox inputs around the beforeinput event and insertLineBreak input type. Verify the behavior with the alert open and closed, then with its inputs changed to an empty array. Done means textarea line breaks work in all of those cases while IonAlert inputs remain functional.

由索引模型根据 Issue 内容生成。