Platform capture

Linux capture uses usbmon. BusScope expects normal-user GUI operation and escalates only the helper action that loads usbmon or applies device ACLs.

Windows capture uses USBPcap. BusScope does not bundle the GPL driver; install USBPcap separately and let the app surface whether USBPcapCMD.exe is reachable.

macOS is out of scope. Do not expect a macOS capture backend, package, or support path.