Get Transfer Metrics

Team-level transfer metrics, bucketed in the customer's local timezone.

Teams are TransferDestination rows matched by the number the call was transferred to; teams sort by missed rate (worst first). Pickup/missed rates are FIRST-QUEUE rates from transfer_outcome plus the transfer_flow snapshot: a call answered only after rolling to a downstream queue counts as missed by the team it was sent to. Hand-off counts, queue waits, and per-extension answer counts come from the flow snapshot (coverage reported, since older calls may lack one). Trends compare against the immediately preceding period of equal length.