Add toast notification for contest readiness in app.py

- Introduced a toast message to inform users when the contest is ready for analysis, enhancing user feedback and experience.
- This addition improves the interactivity of the application by providing immediate visual confirmation of the contest state.

app.py

@@ -466,6 +466,8 @@ if selected_tab == 'Data Load':
         st.session_state['unique_players'] = pd.unique(st.session_state['display_contest_info'][st.session_state['player_columns']].values.ravel('K'))
         st.session_state['unique_players'] = [p for p in st.session_state['unique_players'] if p != 'nan']
 
+        st.toast('Contest ready for analysis!', icon='🎉')
+
 if selected_tab == 'Contest Analysis':
     if 'sport_select' not in st.session_state:
         st.session_state['sport_select'] = st.session_state['sport_init']