• Album covers, station logos and camera pictures follow the app's port (GitHub #84). Home Assistant OS lets you
  publish the app's picture port 8098 under another number in its network settings, for example when another app
  already uses 8098. The screens were still sent links on 8098, so they asked the other app for their pictures and
  showed none. The app now asks the Supervisor which port it published and puts that one in the links. Docker keeps
  SCREEN_CAMERA_PORT and SCREEN_CAMERA_URL as before.
• Tested: tools/check.sh, with new tests for a port published as 8099, a Supervisor that answers nothing usable
  (8098 as before) and Docker's own setting. On a Home Assistant OS bench with the port published as 8099 (8098
  closed), a camera alert on a Guition 4848S040 showed its picture.