staticaddr: high fee versions of the htlc tx

In this commit we add signings of higher fee
htlc txns. The server requires the client to
sign higher fee versions to cover for high fee
environments where pending transactions take a
long time to confirm.

Author: hieblmi

staticaddr/loopin/actions.go

@@ -146,6 +146,18 @@ func (f *FSM) InitHtlcAction(_ fsm.EventContext) fsm.EventType {
 		err = fmt.Errorf("unable to convert server nonces: %w", err)
 		return f.HandleError(err)
 	}
+	f.htlcServerNoncesHighFee, err = toNonces(
+		loopInResp.HtlcServerNoncesHighFee,
+	)
+	if err != nil {
+		return f.HandleError(err)
+	}
+	f.htlcServerNoncesExtremelyHighFee, err = toNonces(
+		loopInResp.HtlcServerNoncesExtremelyHighFee,
+	)
+	if err != nil {
+		return f.HandleError(err)
+	}
 
 	f.htlcServerNoncesHighFee, err = toNonces(
 		loopInResp.HtlcServerNoncesHighFee,
@@ -186,6 +198,7 @@ func (f *FSM) InitHtlcAction(_ fsm.EventContext) fsm.EventType {
 	if fee > maxFee {
 		return f.HandleError(ErrFeeTooHigh)
 	}
+	f.loopIn.HtlcTxExtremelyHighFeeRate = extremelyHighFeeRate
 
 	// Derive the sweep address for the htlc timeout sweep tx.
 	sweepAddress, err := f.cfg.WalletKit.NextAddr(