v2.1.1 multi-launch fix

Scheduled checks launched multiple GUI instances instead of running the CLI.

When Griffin Updater was running as an AppImage, config.python_executable() returned the AppImage path. That path was written into the per-app systemd --user oneshot units as:text

ExecStart=/path/to/Griffin-Updater.AppImage -m griffin_updater.cli check --id <id>

The AppImage entry point () always started the GUI and ignored the CLI arguments, so every timer fire opened a new Griffin Updater window. Manual “Check Now” / “Check All Now” were unaffected because they call the checker in-process.

The frozen entry point now inspects sys.argv and, when invoked with -m griffin_updater.cli … (or the equivalent cleaner forms), dispatches to griffin_updater.cli.main instead of the GUI. Existing unit files continue to work after the AppImage is rebuilt and Regenerate Timers is run.