ButtonShortcode.php

<?php
namespace App\Shortcode;

final class ButtonShortcode implements ShortcodeInterface {
  
    public function getName(): string {
        return 'well';
    }
    public function getArgs(): array {
        return [];
    }
    public function apply(array $attrs, string $content): string {
        return '<button>'.$content.'</button>';
    }
}