test: add PHPUnit test suite with JsonLdBuilder unit tests

16 unit tests covering FAQ, HowTo, Event, Recipe, LocalBusiness,
and VideoObject schema builders plus toScriptTag XSS escaping.
Closes #75

tests/bootstrap.php

@@ -0,0 +1,13 @@
+<?php
+
+/**
+ * @package     MokoSuiteOpenGraph
+ * @subpackage  Tests
+ * @author      Moko Consulting <hello@mokoconsulting.tech>
+ * @copyright   Copyright (C) 2026 Moko Consulting. All rights reserved.
+ * @license     GNU General Public License version 3 or later; see LICENSE
+ */
+
+define('_JEXEC', 1);
+
+require_once __DIR__ . '/../vendor/autoload.php';