DeprecatedTwigTemplateHooks.php

<?php

declare (strict_types=1);
namespace Drupal\deprecated_twig_template\Hook;

use Drupal\Core\Hook\Attribute\Hook;

/**
 * Hook implementations for deprecated_twig_template.
 */
class DeprecatedTwigTemplateHooks {
    
    /**
     * Implements hook_theme().
     */
    public function theme() : array {
        return [
            'deprecated_template' => [
                'variables' => [
                    'message' => NULL,
                ],
                'deprecated' => 'The "deprecated-template.html.twig" template is deprecated in drupal:X.0.0 and is removed from drupal:Y.0.0. Use another template instead. See https://www.example.com',
            ],
        ];
    }

}