fix(keyboard): listen on correct events for keyboard lifecycle (#27569)

Issue number: resolves #27558

---------

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issue. -->

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

The keyboard lifecycle util was always listening on visual viewport
events even when in native environments. The visual viewport API is not
reliable due to how the Ionic webview customizes how it resizes. We
should only be listening on the native keyboard events in native
environments.

https://github.com/ionic-team/capacitor/issues/3730


2e883f3932/keyboard/ios/Plugin/Keyboard.m (L90-L98)

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Keyboard lifecycle util listens on native keyboard events only when in
native environment

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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and migration path for existing applications below. -->


## Other information

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screenshots of how the component looks before and after the change. -->

core/src/utils/keyboard/keyboard.ts

@@ -1,3 +1,5 @@
+import { Keyboard } from '../native/keyboard';
+
 export const KEYBOARD_DID_OPEN = 'ionKeyboardDidShow';
 export const KEYBOARD_DID_CLOSE = 'ionKeyboardDidHide';
 const KEYBOARD_THRESHOLD = 150;
@@ -19,23 +21,35 @@ export const resetKeyboardAssist = () => {
 };
 
 export const startKeyboardAssist = (win: Window) => {
-  startNativeListeners(win);
+  const nativeEngine = Keyboard.getEngine();
 
-  if (!(win as any).visualViewport) {
-    return;
-  }
-
-  currentVisualViewport = copyVisualViewport((win as any).visualViewport);
-
-  (win as any).visualViewport.onresize = () => {
-    trackViewportChanges(win);
-
-    if (keyboardDidOpen() || keyboardDidResize(win)) {
-      setKeyboardOpen(win);
-    } else if (keyboardDidClose(win)) {
-      setKeyboardClose(win);
+  /**
+   * If the native keyboard plugin is available
+   * then we are running in a native environment. As a result
+   * we should only listen on the native events instead of
+   * using the Visual Viewport as the Ionic webview manipulates
+   * how it resizes such that the Visual Viewport API is not
+   * reliable here.
+   */
+  if (nativeEngine !== undefined) {
+    startNativeListeners(win);
+  } else {
+    if (!(win as any).visualViewport) {
+      return;
     }
-  };
+
+    currentVisualViewport = copyVisualViewport((win as any).visualViewport);
+
+    (win as any).visualViewport.onresize = () => {
+      trackViewportChanges(win);
+
+      if (keyboardDidOpen() || keyboardDidResize(win)) {
+        setKeyboardOpen(win);
+      } else if (keyboardDidClose(win)) {
+        setKeyboardClose(win);
+      }
+    };
+  }
 };
 
 /**