fix: [instance] added entity file contents

src/Model/Entity/Instance.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace App\Model\Entity;
+
+use App\Model\Entity\AppModel;
+use Cake\ORM\Entity;
+
+class Instance extends AppModel
+{
+    protected $_accessible = [
+        '*' => true,
+        'id' => false,
+        'uuid' => false,
+    ];
+
+    protected $_accessibleOnNew = [
+        'uuid' => true,
+    ];
+}