feat: entity move

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

shared/lib/Resource/Identifier/EntityIdentifierInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: Sebastian Krupinski <krupinski01@gmail.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace KTXF\Resource\Identifier;
+
+/**
+ * Entity-level identifier (provider + service + collection + entity)
+ */
+interface EntityIdentifierInterface extends CollectionIdentifierInterface {
+
+	/** The entity segment (e.g. "1001") */
+	public function entity(): string;
+
+}