channel: add ResolutionBlob to Incoming+Outgoing HtlcResolution

Similar to the other blobs we have for the commitment output force close
resolution, these blobs will be used to ensure that we have everything
needed to sweep aux HTLCs.

Author: Roasbeef

lnwallet/channel.go

@@ -6959,6 +6959,11 @@ type IncomingHtlcResolution struct {
 	// necessary items required to spend the sole output of the above
 	// transaction.
 	SweepSignDesc input.SignDescriptor
+
+	// ResolutionBlob is a blob used for aux channels that permits a
+	// spender of the output to properly resolve it in the case of a force
+	// close.
+	ResolutionBlob fn.Option[tlv.Blob]
 }
 
 // OutgoingHtlcResolution houses the information necessary to sweep any
@@ -7008,6 +7013,11 @@ type OutgoingHtlcResolution struct {
 	// necessary items required to spend the sole output of the above
 	// transaction.
 	SweepSignDesc input.SignDescriptor
+
+	// ResolutionBlob is a blob used for aux channels that permits a
+	// spender of the output to properly resolve it in the case of a force
+	// close.
+	ResolutionBlob fn.Option[tlv.Blob]
 }
 
 // HtlcResolutions contains the items necessary to sweep HTLC's on chain