fix: resolve [site_name] and other placeholders in checkDir AJAX

BackupDirectory::resolve() only handles [HOME] and [DEFAULT_DIR].
The checkDir AJAX endpoint now uses PlaceholderResolver to also
resolve [site_name], [host], [profile_id], [date], etc. before
checking if the directory exists. This makes the "Resolves to"
display accurate for all placeholder types.

source/packages/com_mokosuitebackup/src/Controller/AjaxController.php

@@ -15,8 +15,10 @@ namespace Joomla\Component\MokoSuiteBackup\Administrator\Controller;
 
 defined('_JEXEC') or die;
 
+use Joomla\CMS\Factory;
 use Joomla\CMS\MVC\Controller\BaseController;
 use Joomla\CMS\Session\Session;
+use Joomla\Component\MokoSuiteBackup\Administrator\Engine\PlaceholderResolver;
 use Joomla\Component\MokoSuiteBackup\Administrator\Engine\SteppedBackupEngine;
 use Joomla\Component\MokoSuiteBackup\Administrator\Engine\SteppedRestoreEngine;
 use Joomla\Component\MokoSuiteBackup\Administrator\Utility\BackupDirectory;
@@ -283,7 +285,32 @@ class AjaxController extends BaseController
 			return;
 		}
 
-		$resolved = BackupDirectory::resolve($rawPath);
+		/* Resolve all placeholders — both directory ([HOME], [DEFAULT_DIR])
+		   and name-level ([site_name], [host], [profile_id], etc.) */
+		$profileId = $this->input->getInt('profile_id', 0);
+
+		if ($profileId > 0) {
+			$db    = Factory::getDbo();
+			$query = $db->getQuery(true)
+				->select('*')
+				->from($db->quoteName('#__mokosuitebackup_profiles'))
+				->where($db->quoteName('id') . ' = ' . $profileId);
+			$db->setQuery($query);
+			$profile = $db->loadObject();
+		}
+
+		if (empty($profile)) {
+			/* No profile context — create a minimal dummy for PlaceholderResolver */
+			$profile = (object) [
+				'id'          => 1,
+				'title'       => 'default',
+				'backup_type' => 'full',
+			];
+		}
+
+		$resolver = new PlaceholderResolver($profile);
+		$withNamePlaceholders = $resolver->resolve($rawPath);
+		$resolved = BackupDirectory::resolve($withNamePlaceholders);
 
 		if (BackupDirectory::hasPlaceholders($resolved)) {
 			$this->sendJson([