Support ListUsers endpoint

[rhamzeh]

Checklist

• I agree to the terms within the OpenFGA Code of Conduct.

Describe the problem you'd like to have solved

We have an RFC for a ListUsers method.

There is an open PR that adds the protobuf definitions.

Describe the ideal solution

The SDK Generator should hide StreamedListUsers (like it does StreamedListObjects) and expose the method in both the OpenFgaApi and OpenFgaClient.

Tasks

• Hide StreamedListUsers
• JS SDK: ListUsers openfga/js-sdk#97
• Go SDK: ListUsers openfga/go-sdk#81
• .NET SDK: ListUsers openfga/dotnet-sdk#57
• Python SDK: ListUsers openfga/python-sdk#94
• Java SDK: ListUsers @ewanharris

Per-SDK Tasks

• Regenerate the SDK to add the appropriate interfaces and methods to OpenFgaApi
• Add tests for ListUsers in OpenFgaApi
• Add ListUsers to OpenFgaClient
• Add tests for ListUsers in OpenFgaClient

Alternatives and current workarounds

No response

References

No response

Additional context

No response