This release supports both v2/v3 handling (with client_secret) and v4 (with only client_id). If your client_id starts with 4P don't bother filling in the client_secret during setup.
Attempt to fix reconnection issues, but locking/unlocking my bike with the app or physically now actually reproduces the state in Home Assistant (fixing #4) - though in test I put the refresh time at 20 seconds. In the release it is still at 10 minutes (you can change this in the code though, it's in custom_components/stromer/__init__.py - if time allows I will add this as a configurable option. (I know how to do it in config_flow, just need some spare time on my hands)