TUN-8701: Simplify flow registration logs for datagram v3

To help reduce the volume of logs during the happy path of flow registration, there will only be one log message reported when a flow is completed.

There are additional fields added to all flow log messages:
1. `src`: local address
2. `dst`: origin address
3. `durationMS`: capturing the total duration of the flow in milliseconds

Additional logs were added to capture when a flow was migrated or when cloudflared sent off a registration response retry.

Closes TUN-8701

ingress/origin_udp_proxy.go

@@ -39,7 +39,7 @@ func DialUDPAddrPort(dest netip.AddrPort) (*net.UDPConn, error) {
 	// address as context.
 	udpConn, err := net.DialUDP("udp", nil, addr)
 	if err != nil {
-		return nil, fmt.Errorf("unable to create UDP proxy to origin (%v:%v): %w", dest.Addr(), dest.Port(), err)
+		return nil, fmt.Errorf("unable to dial udp to origin %s: %w", dest, err)
 	}
 
 	return udpConn, nil