fix multi-geometry issue

app.py

@@ -70,11 +70,8 @@ else:
             file_url = f"https://drive.google.com/uc?id={ID}"
 
     input_gdf = preprocess_gdf(gpd.read_file(file_url))
-    if len(input_gdf) != 1:
-        st.error(
-            f"Expecting only one geometry per KML, but found {len(input_gdf)} geometries. Please fix the KML or provide another KML."
-        )
-        st.stop()
+    if len(input_gdf) > 1:
+        st.warning(f"Only the first polygon in the KML will be processed; all other geometries will be ignored.")
     st.session_state.input_gdf = input_gdf
     # st.toast("Data loaded and cached")