Firstly update your list variable to have a container object:
var lists = { items: [{ name: 'test' }] };
Then expose access to the list through the factory, eg:
factory.getLists = function() {
return lists;
}
Then set a scope var in your controller:
$scope.lists = ListFactory.getLists();
Then whenever the child_added
event is triggered, update the lists.items, and the $scope
from the controller should reflect the changes.