gods-eye-view/changelog.d/1576-transit-bikeshare-coverage-prompt.md

- Say why Transit and Bike Share are empty outside coverage. Over a city with
  no feed or system (London, Tokyo) their Layers rows say so and count the
  covered regions or systems, or say how low to fly, instead of `never`;
  leaving coverage clears the last-update time (German, @gekh, #1576).