bug: modal with swipe gesture should call onWillDismiss once dismiss is confirmed

### Prerequisites

- [X] I have read the [Contributing Guidelines](https://github.com/ionic-team/ionic-framework/blob/main/.github/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

v7.x

### Current Behavior

When swiping to dismiss a modal, `onWillDismiss` is called after modal dismiss animation completes.

### Expected Behavior

`onWillDismiss` should be called as soon as Ionic determines if the modal should be dismissed. For swipe to dismiss, I would expect this to happen after the user lifts their finger off the screen following the swipe to dismiss gesture, if Ionic calculates that the modal should dismiss.

### Steps to Reproduce

1. Run reproduction
2. Swipe to dismiss
3. Observe alert incorrectly presents after animation completes
4. Additionally, observe tapping "close" button correctly presents alert *before* animation starts

### Code Reproduction URL

https://stackblitz.com/edit/u8qciq-6x7ht2?file=src%2Fmain.tsx

### Ionic Info

N/A - running codepen

### Additional Information

Potentially related? https://github.com/ionic-team/ionic-framework/issues/17600

I am tagging this as a bug because when dismissing though a non-swipe button (programmatically or through dismiss button),`onWillDismiss` is correctly called *before* the dismiss animation starts.

This is a problem for my app because I would like to dismiss the keyboard as soon as I know the modal will dismiss, not after the modal finishes animating out.

### Swipe down - Incorrect behavior

https://github.com/ionic-team/ionic-framework/assets/2166114/b6066444-482d-4c80-98b1-766fe6d32a22

### Tap to dismiss - Correct behavior

https://github.com/ionic-team/ionic-framework/assets/2166114/64763dbb-6be0-4725-98b7-1b56a44cdd0b

Start by running the reproduction in src/main.tsx from the linked StackBlitz project and compare swipe dismissal with the close-button path. Trace the modal's swipe-confirmation flow and callback timing. Done means onWillDismiss fires immediately after a swipe is confirmed, before the dismiss animation, while the existing button behavior remains unchanged.

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