set default retrieval to 4

app.py

@@ -105,7 +105,7 @@ def sidebar() :
         st.markdown("# Retrieval Settings")
         st.session_state.rag_enabled = st.toggle("Activate RAG", value=True)
         st.session_state.top_k = st.slider(label="Documents to retrieve",
-                min_value=1, max_value=20, value=10, disabled=not st.session_state.rag_enabled)
+                min_value=1, max_value=20, value=4, disabled=not st.session_state.rag_enabled)
         st.markdown("---")
     
     def model_analytics() :