Backend

Use GraphHopper API to get bounds for the current data set and include it in the response sent to the client upon subscribing to the route topic.

Question: do we want bounds for:

1. The whole geographical region that is currently loaded (independent on cities that we have)?
2. The demo data set (e.g. when the current route is empty)?
3. The current route (unless it's empty)?

Frontend

Update state with the bounds, use it as props for the TspMap component, calculate the appropriate zoom level and center coordinates.