Fix condition for stack statistics display in app.py: update header check to use 'columns' instead of 'headers' for accurate data retrieval.

app.py

@@ -1315,7 +1315,7 @@ with tab2:
             )
         
         with stack_stats_col:
-            if 'Stack' in display_frame.headers:
+            if 'Stack' in display_frame.columns:
                 stack_stats = []
                 stack_columns = [col for col in display_frame.columns if col.startswith('Stack')]
                 for stack in stack_dict.values():