Backend: monitor_thread sends periodic monitor_heartbeat events (every
5s) with elapsed time, packet count, and device count so the frontend
knows monitoring is active.
Frontend: new monitoring overlay replaces scan progress bar when
auto-monitor starts. Shows pulsing green indicator, ARFCN being
monitored, live elapsed timer, packet/device counts, and
"Listening..."/"Capturing" activity state.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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