chore: rename src/ to source/ per MokoStandards convention

Update all references in Makefile, manifest.xml, .gitignore, and CI
workflows (ci-joomla, pr-check, repo-health) to use source/ as the
primary directory with src/ as a fallback for compatibility.

Authored-by: Moko Consulting
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

source/packages/com_mokobackup/src/Controller/ProfileController.php

@@ -0,0 +1,20 @@
+<?php
+
+/**
+ * @package     MokoJoomBackup
+ * @subpackage  com_mokobackup
+ * @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
+ */
+
+namespace Joomla\Component\MokoBackup\Administrator\Controller;
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\MVC\Controller\FormController;
+
+class ProfileController extends FormController
+{
+	protected $text_prefix = 'COM_MOKOBACKUP_PROFILE';
+}