chore: cleanup, add PHPStan type annotations

src/Command/BpnXmlSyncCommand.php

@@ -200,6 +200,7 @@ class BpnXmlSyncCommand extends Command
     }
 
     /**
+     * @return array<string, int>
      * @throws FilesystemException
      */
     private function syncFiles(SymfonyStyle $io): array