- Introduced `is_builtin` property in the model configuration to identify builtin models.
- Updated frontend components to display a tag for builtin models in the ModelSelector and ModelSettings.
- Enhanced the ModelEditorDialog to prevent editing and deletion of builtin models.
- Implemented logic in the backend to hide sensitive information for builtin models and restrict their modification.
- Added informative UI elements to clarify the nature of builtin models in the settings and editor views.