Detailed changes can be found from ChangeLog.
Check the latest release you have by getting new tags with git fetch --tags then running git describe.
Write this version number down somewhere.
Git users can just run git pull. If the dependencies have changed, you'll also have to run uv sync again to upgrade them. Remember to use --group NAME or --all-groups (for everything) or uv will uninstall unwanted dependencies which you may actually want to keep.