I try to create images from the backend October CMS when adding a model using a third-party API by clicking on the button and return the response of each image to the File Upload widget (similar to Dropzone).

Question: How to return the answer image and immediately attach to the dropzone field? So that after saving the model, the field is attached through a relation.

Request from the button:

<button data-request="onMakeScreenshots" id="screenshots" data-request-data="url: 'http://site.ru/'" class="btn btn-primary">Создать скриншоты</button>

The controller method of this model:
<pre><code>
public function onMakeScreenShots() {
    $url = post('url');       

    $client = new Client();
    $request = $client->get('http://mini.s-shot.ru/' . '1280x800' . '/' . '1280' . '/' . '/jpeg/?' . $url);
    $response = $request->getBody();
    $screenshot_name = str_random(40) . '.jpg';
    $file = (new File)->fromData($response,  $screenshot_name);

    return [
        '#FileUpload-formScreenshots-screenshots' => $file
    ];
}
</code></pre>

The binary code is returned, I try to create a file with the name and transfer it to the field with a dropzone, but this does not work.