Help: Casts not happening before API response

Regarding the use of https://laravel.com/docs/master/eloquent-mutators#attribute-casting with example:

```
'array',
];
}
```

When I use the native PHP accessor

```
$user = \App\User::find(1);
$user->options['thing'] = 'stuff';
$user->save();
```

The JSON is automagically converted to an array, the key is updated, and then converted back to JSON when saved. This works as expected.
With Dingo in the mix I am responding to an API request:

```
// SomeController.php
public function listUsers()
{
$users = User::all();
// At this point each $user->options appears to still be a STRING of JSON data, it is not de-serialized until I try to access it as a $user->options property.
$response = [
'success' => true,
'message' => '',
'users' => $users,
];
return response()->json($response);
// My hope is that the Dingo response would notice that there are casts and somehow de-serialize the data before building a JSON response for the user. Is this an incorrect use?
}
```

Dingo is not responding with the user array like in the accessor, but it is instead responding with the string of JSON. I can manually decode this JSON string within the Dingo JSON response manually, but that is rather odd to have to do.

Is there a better way to respond to the request that will properly de-serialize the JSON $user->options property before sending the response back to the user? Or is this not currently supported?