Refactor player and stack column handling in app.py to accommodate combined dataframe

- Updated logic to determine player and stack columns based on the presence of 'portfolio_df' in session state, enhancing data processing flexibility.
- Ensured vectorized string operations are applied to the correct dataframe, improving data integrity and user experience.

app.py

@@ -230,13 +230,20 @@ with tab2:
     excluded_cols = ['BaseName', 'EntryCount']
     exclude_stacks = ['BaseName', 'EntryCount', 'SP', 'SP1', 'SP2', 'P1', 'P2']
     if 'Contest' in st.session_state and 'display_contest_info' not in st.session_state:
-        st.session_state['player_columns'] = [col for col in st.session_state['Contest'].columns if col not in excluded_cols]
-        st.session_state['stack_columns'] = [col for col in st.session_state['Contest'].columns if col not in exclude_stacks]
+        if 'portfolio_df' in st.session_state:
+            st.session_state['player_columns'] = [col for col in st.session_state['combined_df'].columns if col not in excluded_cols]
+            st.session_state['stack_columns'] = [col for col in st.session_state['combined_df'].columns if col not in exclude_stacks]
+        else:
+            st.session_state['player_columns'] = [col for col in st.session_state['Contest'].columns if col not in excluded_cols]
+            st.session_state['stack_columns'] = [col for col in st.session_state['Contest'].columns if col not in exclude_stacks]
         print(st.session_state['player_columns'])
         
         # Vectorized string operations
         for col in st.session_state['player_columns']:
-            st.session_state['Contest'][col] = st.session_state['Contest'][col].astype(str).str.strip()
+            if 'portfolio_df' in st.session_state:
+                st.session_state['combined_df'][col] = st.session_state['combined_df'][col].astype(str).str.strip()
+            else:
+                st.session_state['Contest'][col] = st.session_state['Contest'][col].astype(str).str.strip()
     
         # Create mapping dictionaries
         st.session_state['map_dict'] = {