- Modified _create_widgets() to conditionally create filter area only for admin users
- Modified _create_filter_checkboxes() to return early for non-admin users
- This prevents AttributeError when accessing self.filter_frame for User users
- Admin users retain full filtering functionality
- Fixes the 'MaterialTypeManagementDialog' object has no attribute 'filter_frame' error
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>