Improve heatmap visibility: increase radius and opacity, reduce blur for clearer patterns

Remove CircleMarker points visualization, keep only smooth HeatMap gradient

Improve heatmap rendering: wrap HeatMap in FeatureGroup and enhance marker visualization

Add CircleMarker fallback visualization to both single and combined heatmaps

Fix folium heatmaps: Use streamlit_folium for proper Streamlit integration

Fresh start: Clean repo without large file history - ready for HF Spaces