LGTM. What was the motivation? I'm not against uv, but whatever we do here should work with plain pip too. If we had issues with pip we should try to solve them. If it is just speed, merge away!

As part of our test suite, Frank and I added integration tests with some popular downstream packages (geopandas and streamlit-folium.) In the github workflow we used to install streamlit-folium using pip and then install the current folium into that environment and then running the tests from streamlit-folium. That stopped working because the streamlit-folium package switched to uv.