Fix Back to Mode Selection buttons functionality

- Add Back buttons at the top of each mode interface
- Create go_back_to_mode_selection helper function
- Bind click handlers for all three Back buttons
- Properly update interface visibility when returning to mode selection
- Resolves issue where Back buttons were not working

src/interface/enhanced_verification_interface.py

@@ -197,15 +197,33 @@ class EnhancedVerificationInterface:
                 # Individual mode interfaces (initially hidden)
                 enhanced_dataset_interface = gr.Row(visible=False)
                 with enhanced_dataset_interface:
-                    enhanced_dataset_ui = EnhancedVerificationUIComponents.create_enhanced_dataset_interface_with_handlers()
+                    with gr.Column():
+                        gr.Markdown("# 📊 Enhanced Dataset Mode")
+                        gr.Markdown("Select and customize test datasets for verification.")
+                        back_from_dataset_btn = gr.Button("← Back to Mode Selection", size="sm")
+                        gr.Markdown("---")
+                        # Embed the actual interface
+                        enhanced_dataset_ui = EnhancedVerificationUIComponents.create_enhanced_dataset_interface_with_handlers()
                 
                 manual_input_interface = gr.Row(visible=False)
                 with manual_input_interface:
-                    manual_input_ui = EnhancedVerificationUIComponents.create_manual_input_interface()
+                    with gr.Column():
+                        gr.Markdown("# ✏️ Manual Input Mode")
+                        gr.Markdown("Enter individual messages for immediate classification and verification.")
+                        back_from_manual_btn = gr.Button("← Back to Mode Selection", size="sm")
+                        gr.Markdown("---")
+                        # Embed the actual interface
+                        manual_input_ui = EnhancedVerificationUIComponents.create_manual_input_interface()
                 
                 file_upload_interface = gr.Row(visible=False)
                 with file_upload_interface:
-                    file_upload_ui = EnhancedVerificationUIComponents.create_file_upload_interface()
+                    with gr.Column():
+                        gr.Markdown("# 📁 File Upload Mode")
+                        gr.Markdown("Upload CSV or XLSX files for batch processing.")
+                        back_from_file_btn = gr.Button("← Back to Mode Selection", size="sm")
+                        gr.Markdown("---")
+                        # Embed the actual interface
+                        file_upload_ui = EnhancedVerificationUIComponents.create_file_upload_interface()
             
             # Event handlers
             def initialize_interface():
@@ -511,6 +529,55 @@ class EnhancedVerificationInterface:
                 ]
             )
             
+            # Helper function to go back to mode selection
+            def go_back_to_mode_selection():
+                """Return to mode selection screen."""
+                return (
+                    gr.Row(visible=True),   # mode_selection_section
+                    gr.Row(visible=False),  # enhanced_dataset_interface
+                    gr.Row(visible=False),  # manual_input_interface
+                    gr.Row(visible=False),  # file_upload_interface
+                    None,                   # current_mode_state
+                    "✅ Returned to mode selection"  # status_message
+                )
+            
+            # Bind Back buttons for each mode
+            back_from_dataset_btn.click(
+                go_back_to_mode_selection,
+                outputs=[
+                    mode_selection_section,
+                    enhanced_dataset_interface,
+                    manual_input_interface,
+                    file_upload_interface,
+                    current_mode_state,
+                    status_message
+                ]
+            )
+            
+            back_from_manual_btn.click(
+                go_back_to_mode_selection,
+                outputs=[
+                    mode_selection_section,
+                    enhanced_dataset_interface,
+                    manual_input_interface,
+                    file_upload_interface,
+                    current_mode_state,
+                    status_message
+                ]
+            )
+            
+            back_from_file_btn.click(
+                go_back_to_mode_selection,
+                outputs=[
+                    mode_selection_section,
+                    enhanced_dataset_interface,
+                    manual_input_interface,
+                    file_upload_interface,
+                    current_mode_state,
+                    status_message
+                ]
+            )
+            
             # Bind session resumption buttons
             resume_session_btn.click(
                 resume_selected_session,