Xamarin.Firebase packages needs to update to support .NET9.0 with Android35

### Description

We have a mobile application built using .NET MAUI targeting .NET 8.0 and Android API level 34. As per the new Google Play policy, all app updates must target Android API level 35 by August 31, 2025.

To comply with this requirement, we are in the process of upgrading our app to .NET 9.0 with Android API level 35. However, we’ve encountered a significant blocker: the Xamarin.Firebase packages (especially Xamarin.Firebase.Crashlytics,Xamarin.Firebase.Analytics) are not currently compatible with .NET 9.0.

While some early versions of these packages appear to be available for .NET 10.0, that version is still in preview and not officially released. This leaves us unable to move forward with .NET 9.0 while maintaining Firebase support, which is critical for crash reporting and analytics in our production environment.

We kindly request:

Official support for Firebase packages (especially Crashlytics & Analytics) compatible with .NET 9.0 and Android API 35.
Guidance or timelines on when these packages will be available, if already in progress.
This support is essential for teams like ours who need to meet Google Play’s API requirements while maintaining production-grade monitoring.

Thank you!