Initial commit: Horux Backend API

- API REST para gestion de facturas electronicas mexicanas (CFDI)
- Laravel 9 con autenticacion OAuth 2.0 (Passport)
- Integracion con Syntage, Clerk y Facturama
- 30 modelos Eloquent, 39 controladores
- Documentacion completa en /docs

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/Unit/ExampleTest.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Tests\Unit;
+
+use PHPUnit\Framework\TestCase;
+
+class ExampleTest extends TestCase
+{
+    /**
+     * A basic test example.
+     *
+     * @return void
+     */
+    public function test_that_true_is_true()
+    {
+        $this->assertTrue(true);
+    }
+}