Expose A/B Testing Variant Name/ID directly via RemoteConfig SDK

## What feature would you like to see?

Currently, when using Firebase Remote Config and A/B Testing, the client SDK only returns the value of a specific parameter. There is no direct way to determine which variant (e.g., "Control Group", "Variant A", "Variant B") the user has been assigned to on the client side.

While this data is automatically tracked in Google Analytics, it creates friction for developers who need to know the active variant within the app logic.

## How would you use it?

We want to get current variant_name and make differences in our application. And store variant_name in our database.