[Feature]: Provide an iOS API similar to WebViewListener on Android

[hbordersTwitch]

Description

Android has a WebViewListener to observe WebView health/progress. iOS should have a similar API

Platforms

• iOS
• Android
• Web

Request or proposed solution

On Android, WebViewListener has the following callbacks:

onPageLoaded
onReceivedError
onReceivedHttpError
onPageStarted
onRenderProcessGone

These are all available on iOS via WKNavigationDelegate
onPageLoaded: func webView(WKWebView, didFinish: WKNavigation!)
onReceivedError: func webView(WKWebView, didFailProvisionalNavigation: WKNavigation!, withError: any Error)
onReceivedHttpError: func webView(WKWebView, decidePolicyFor: WKNavigationResponse, decisionHandler: (WKNavigationResponsePolicy) -> Void)
onPageStarted: func webView(WKWebView, didStartProvisionalNavigation: WKNavigation!)
onRenderProcessGone: func webViewWebContentProcessDidTerminate(WKWebView)

Alternatives

CAPWebView.capacitorDidLoad gets called just before capacitor loads the underlying request within the WKWebView, so consumers could create their own WKNavigationDelegate to wrap the existing WebViewDelegationHandler that is set on the WKWebView, and then wrap all of the above methods and delegate into the WebViewDelegationHandler via its conformance to WKNavigationDelegate. This is complex and brittle since it's using API that I assume Capacitor doesn't want consumers to access.

Additional Information

Thanks so much for this project!