Aggregation/GroupBy queries in Datastore

### 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

Not applicable

### Amplify Categories

GraphQL API, DataStore

### Gradle script dependencies

```groovy
// Put output below this line

```

### Environment information

```
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```

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

_No response_

### Describe the feature request

Data aggregation is a very common use case (e.g. giving totals, average values over time, aggregated metrics...).

Is this a feature under development or with a publicly known roadmap? What would the current workarounds for this feature be?

### Initialization steps (if applicable)

_No response_

### Code Snippet

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

```

### amplifyconfiguration.json

_No response_

### GraphQL Schema

```graphql
// Put your schema below this line

```

### Additional information and screenshots

_No response_

No source files, tests, or entry points are named, and the schema and code sections are empty. Start by reviewing the Android DataStore query APIs and project roadmap to determine whether aggregation and GroupBy are supported or planned; a complete issue would need a defined scope, workaround or implementation target, and acceptance criteria.

Written by the indexing model from the issue text.