check isAdmin and auth

checkAuth.php

@@ -0,0 +1,14 @@
+<?php
+session_start();
+header('Content-Type: application/json');
+
+if (!isset($_SESSION['authenticated']) || $_SESSION['authenticated'] !== true) {
+    echo json_encode(["authenticated" => false]);
+    exit;
+}
+
+echo json_encode([
+    "authenticated" => true,
+    "isAdmin" => isset($_SESSION["isAdmin"]) ? $_SESSION["isAdmin"] : false
+]);
+?>