bug: Popover incorrectly rendered when css zoom is set on html element

### 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

When CSS zoom is set on html element to value other than 1, popover gets drawn incorrectly.
It is positioned in the incorrect place. Setting size attribute to cover makes size of popover to be also incorrect.

### Expected Behavior

Popover should be sized and positioned correctly regardless of zoom.

### Steps to Reproduce

1. Set CSS zoom on html element to anything other than 1 (ex. 1.5)
2. Open popover by clicking on a button

### Code Reproduction URL

https://stackblitz.com/edit/lelnqysr?file=src%2Fglobal.css

### Ionic Info

Ionic:

Ionic CLI : 7.2.1 (C:\Users\USER\AppData\Roaming\npm\node_modules\@ionic\cli)
Ionic Framework : @ionic/angular 8.7.16
@angular-devkit/build-angular : not installed
@angular-devkit/schematics : 20.1.0
@angular/cli : 20.1.0
@ionic/angular-toolkit : 11.0.1

Utility:

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

System:

NodeJS : v22.20.0 (C:\Program Files\nodejs\node.exe)
npm : 11.6.2
OS : Windows 10

### Additional Information

Changing the zoom level of the html element is mentioned in Ionic documentation.
https://ionicframework.com/docs/layout/dynamic-font-scaling#chrome-for-android

Start with the linked StackBlitz reproduction and its src/global.css, setting CSS zoom on html before opening the popover. Trace the popover's sizing and positioning behavior under zoom; done means it remains correctly sized and positioned, including when size is set to cover.

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