Provide a way to identify chart attachment added to chart render array

I added two properties, as I think this would be more helpful for users when separated:

$chart[$key]['#view_id'] = $this->view->id();
$chart[$key]['#chart_attachment_id'] = $child_display_handler->display['id'];

We do have $chart['#view']. The users can get the view ID from it. We might also need to document this at https://git.drupalcode.org/project/charts/-/blob/5.1.x/charts.api.php?re....

Automatically closed - issue fixed for 2 weeks with no activity.