designtopack/public/site/plugins/comments/index.php

<?php

F::loadClasses([
  'adrienpayet\\comments\\BaseComment' => __DIR__ . '/src/BaseComment.php',
  'adrienpayet\\comments\\Comment' => __DIR__ . '/src/Comment.php',
  'adrienpayet\\comments\\Reply' => __DIR__ . '/src/Reply.php'
]);

Kirby::plugin('adrienpayet/kirby4-comments', [
  'routes' => [
    require(__DIR__ . '/routes/create.php'),
    require(__DIR__ . '/routes/update.php'),
    require(__DIR__ . '/routes/delete.php'),
    require(__DIR__ . '/routes/reply.php'),
  ]
]);