feat: Enable configuration of offline mode on all platforms

[morzel85]

Plugin(s)

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

Current problem

Currently offline document read is not supported on Web platform. Executing this code:

const { snapshot } = await FirebaseFirestore.getDocument({
  reference: 'someDocPathHere',
});

Gives such error: "FirebaseError: Failed to get document because the client is offline"

Preferred solution

capacitor-firebase should expose configuration for enabling/disabling offline mode on all platforms where Firestore itself can support it.

Alternative options

No response

Additional context

https://github.com/capawesome-team/capacitor-firebase/discussions/713

Before submitting

• [X] I have read and followed the feature request guidelines.
• [X] I have attached links to possibly related issues and discussions.