Keep the macOS kiosk on its own desktop

On macOS the kiosk followed you to every desktop, so it flashed on top of other apps in full screen whenever you switched to them.

• Fixed the kiosk flashing over other full-screen apps when switching desktops on macOS
• Updated the kiosk to stay on its own desktop like any other app: swipe away to use another app, then swipe back or click its Dock icon to return
• Kept the kiosk full screen, with the Dock and menu bar hidden while it is in front