split principal types into different subclasses, added principal factory, implemented principal friendlyNames and FullHierarchyNames, added parentOrganizationId attribute to organizations

lib/Model/UserPrincipal.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace OCA\OrganizationFolders\Model;
+
+use OCP\IUserManager;
+use \OCP\IUser;
+
+use OCA\OrganizationFolders\Enum\PrincipalType;
+
+class UserPrincipal extends Principal {
+    private ?IUser $user;
+
+    public function __construct(
+        private IUserManager $userManager,
+        private string $id,
+	) {
+        try {
+            $this->user = $this->userManager->get($id);
+            $this->valid = !is_null($this->user);
+        } catch (\Exception $e) {
+            $this->valid = false;
+        }
+    }
+
+    public function getType(): PrincipalType {
+		return PrincipalType::USER;
+	}
+
+    public function getId(): string {
+		return $this->id;
+	}
+
+    public function getFriendlyName(): string {
+        return $this->user?->getDisplayName();
+    }
+}