Geek KVM screen agent: sends this PC's screen to the dongle.

Linux (GNOME): bash install_agent_service.sh      (no sudo; it installs a user service and finds the dongle plugged into this PC over USB)
Windows: double-click install_agent.bat (no administrator rights; it installs Python 3.12 with winget if needed, sets up the agent under
         %LOCALAPPDATA%\geek-kvm-agent and starts it at every logon; install_agent.bat /uninstall removes it)
         If it does not work: install_agent.bat /diagnose  (tests the USB port, the dongle, the network and the screen capture; send the output)
macOS: pip install -r requirements.txt, then python screen_agent.py   (python screen_agent.py --diagnose finds problems on any system)
Keep the files in one folder. Python 3.10 or newer is needed.
