Add dummy file so phpcs and phpstan can be tested

Author: borkweb

src/DummyForAnalysis.php

@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * DummyForAnalysis class file.
+ *
+ * @package WordPress\AiClient
+ */
+
+declare(strict_types=1);
+
+namespace WordPress\AiClient;
+
+/**
+ * Class DummyForAnalysis
+ *
+ * This is a dummy class for testing that phpcs and phpstan are working.
+ * It should be removed once we have a real class.
+ */
+class DummyForAnalysis
+{
+    public function dummy(): void
+    {
+        // Placeholder.
+    }
+}