lnwallet: add FundingBlob method to LightningChannel

lnwallet/channel.go

@@ -9564,3 +9564,16 @@ func (lc *LightningChannel) LocalCommitmentBlob() fn.Option[tlv.Blob] {
 		return newBlob
 	})(localBalance)
 }
+
+// FundingBlob returns the funding custom blob.
+func (lc *LightningChannel) FundingBlob() fn.Option[tlv.Blob] {
+	lc.RLock()
+	defer lc.RUnlock()
+
+	return fn.MapOption(func(b tlv.Blob) tlv.Blob {
+		newBlob := make([]byte, len(b))
+		copy(newBlob, b)
+
+		return newBlob
+	})(lc.channelState.CustomBlob)
+}