[Feature]: Overriding WebViewDelegationHandler

### Description

I can't seem to find a way to override the standard WebViewDelegationHandler

### Platforms

- [x] iOS
- [ ] Android
- [ ] Web

### Request or proposed solution

I was trying to find a way to use my own "WebViewDelegationHandler" and looking at this issue https://github.com/ionic-team/capacitor/issues/6605

In this PR https://github.com/ionic-team/capacitor/pull/6894 I see that someone correctly abstracted the instantiation of certain object (e.g. the new "func router()" that can be found [here](https://github.com/ionic-team/capacitor/blob/main/ios/Capacitor/Capacitor/CAPBridgeViewController.swift#L112-L114).

However, the instantiation of "WebViewDelegationHandler" is in a private function [here](https://github.com/ionic-team/capacitor/blob/main/ios/Capacitor/Capacitor/CAPBridgeViewController.swift#L56) basically making it extremely hard to subclass.

Would a PR to move this into an extensible function (like "Router") be welcome?

### Alternatives

_No response_

### Additional Information

_No response_