Fix all Gradio component returns to use gr.update()

- Fixed refresh_files to use gr.update() instead of returning gr.Dropdown
- Fixed all gr.File returns in run_with_clean_models to use gr.update()
- This should fully resolve the API schema TypeError in HF Spaces

validator_gui.py

@@ -510,7 +510,7 @@ class ValidatorGUI:
                 
                 def refresh_files():
                     files = self.get_excel_files()
-                    return gr.Dropdown(choices=files, value=files[0] if files else None)
+                    return gr.update(choices=files, value=files[0] if files else None)
                 
                 def clean_model_name(model):
                     # Remove "(recommended)" suffix if present
@@ -546,13 +546,13 @@ class ValidatorGUI:
                             if len(result) == 3:
                                 result_text, result_file, stats = result
                                 if result_file:
-                                    yield result_text, gr.File(value=result_file, visible=True), stats
+                                    yield result_text, gr.update(value=result_file, visible=True), stats
                                 else:
-                                    yield result_text, gr.File(visible=False), stats
+                                    yield result_text, gr.update(visible=False), stats
                             else:
-                                yield result[0], gr.File(visible=False), result[1] if len(result) > 1 else ""
+                                yield result[0], gr.update(visible=False), result[1] if len(result) > 1 else ""
                     else:
-                        yield "No file selected", gr.File(visible=False), ""
+                        yield "No file selected", gr.update(visible=False), ""
                 
                 file_dropdown.change(update_file_info, inputs=[file_dropdown], 
                                     outputs=[file_info, end_question])