feat: extend authentication to expose the `idTokenChange` event

[cjhoward92]

Plugin(s)

• [ ] Analytics
• [ ] App
• [ ] App Check
• [X] Authentication
• [ ] Crashlytics
• [ ] Cloud Firestore
• [ ] Cloud Functions
• [ ] Cloud Messaging
• [ ] Cloud Storage
• [ ] Performance
• [ ] Remote Config

Current problem

The idTokenChange event is not exposed. Also. on iOS, the auth change listener isn't correct. It should be like so https://firebase.google.com/docs/auth/ios/manage-users

Preferred solution

Do the things.

Alternative options

There are none - we need this.

Additional context

No response

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• [X] I have attached links to possibly related issues and discussions.