Added the permission models

lib/models/TeamPermission.php

@@ -0,0 +1,37 @@
+<?php
+declare(strict_types=1);
+namespace yii\gitea\models;
+
+use Enum\{EnumTrait};
+
+/**
+ * Defines the permission of a Gitea status.
+ */
+final class TeamPermission {
+  use EnumTrait;
+
+  /**
+   * @var string The team has the administrator permission.
+   */
+  const ADMIN = 'admin';
+
+  /**
+   * @var string The team doesn't have any permission.
+   */
+  const NONE = 'none';
+
+  /**
+   * @var string The team has the owner permission.
+   */
+  const OWNER = 'owner';
+
+  /**
+   * @var string The team has the read permission.
+   */
+  const READ = 'read';
+
+  /**
+   * @var string The team has the write permission.
+   */
+  const WRITE = 'write';
+}