lnwire: add blinding point to update_add_htlc TLVs

Add blinding points to update_add_htlc. This TLV will be set for
nodes that are relaying payments in blinded routes that are _not_
the introduction node.

peer/brontide.go

@@ -45,6 +45,7 @@ import (
 	"github.com/lightningnetwork/lnd/queue"
 	"github.com/lightningnetwork/lnd/subscribe"
 	"github.com/lightningnetwork/lnd/ticker"
+	"github.com/lightningnetwork/lnd/tlv"
 	"github.com/lightningnetwork/lnd/watchtower/wtclient"
 )
 
@@ -1985,8 +1986,19 @@ func messageSummary(msg lnwire.Message) string {
 			msg.FeeSatoshis)
 
 	case *lnwire.UpdateAddHTLC:
-		return fmt.Sprintf("chan_id=%v, id=%v, amt=%v, expiry=%v, hash=%x",
-			msg.ChanID, msg.ID, msg.Amount, msg.Expiry, msg.PaymentHash[:])
+		var blindingPoint []byte
+		msg.BlindingPoint.WhenSome(
+			func(b tlv.RecordT[lnwire.BlindingPointTlvType,
+				*btcec.PublicKey]) {
+
+				blindingPoint = b.Val.SerializeCompressed()
+			},
+		)
+
+		return fmt.Sprintf("chan_id=%v, id=%v, amt=%v, expiry=%v, "+
+			"hash=%x, blinding_point=%x", msg.ChanID, msg.ID,
+			msg.Amount, msg.Expiry, msg.PaymentHash[:],
+			blindingPoint)
 
 	case *lnwire.UpdateFailHTLC:
 		return fmt.Sprintf("chan_id=%v, id=%v, reason=%x", msg.ChanID,