Zero-Tap Sign-In support

### Before opening, please confirm:

- [x] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-android/issues?q=is%3Aissue+) and [discussions](https://github.com/aws-amplify/amplify-android/discussions).

### Language and Async Model

Kotlin

### Amplify Categories

Authentication

### Gradle script dependencies

```kotlin
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```

### Environment information

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### Please include any relevant guides or documentation you're referencing

_No response_

### Describe the feature request

On 26 August 2026, Google published a blog post, where one of the items discussed was improving device migration, accomplished by most class of apps required to support Zero-Tap Sign-In.

https://android-developers.googleblog.com/2026/08/app-quality-memory-optimization-secure-onboarding.html

My reading of the Amplify Android code is that as-is, that's not supported.
Specifically, EncryptedKeyValueRepository.kt stores a file under the "no backup" directory.

> EncryptedSharedPreferences may have been backed up by the application, but will be unreadable due to the KeyStore record being lost. To prevent an unreadable EncryptedSharedPreferences, we append a suffix to the name with a UUID created in the noBackupFilesDir

Is this something the team is aware of, and be able to address before any deadlines?

### Initialization steps (if applicable)

_No response_

### Code Snippet

```kotlin
// Put your code below this line.

```

### Configuration File

_No response_

### GraphQL Schema

```graphql
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```

### Additional information and screenshots

_No response_