Implement Phase 3 of packet-loss diagnostics: switch-port congestion and IGMP-querier flapping detection. See [PACKET-LOSS-DIAGNOSTICS](https://github.com/HamSCI/sigmond/blob/main/docs/PACKET-LOSS-DIAGNOSTICS.md).
Implement Phase 3 of packet-loss diagnostics: switch-port congestion and IGMP-querier flapping detection. See PACKET-LOSS-DIAGNOSTICS.