[custom channels 1/5]: extract PART1 from mega staging branch

chainreg/chainregistry.go

@@ -24,6 +24,7 @@ import (
 	"github.com/lightningnetwork/lnd/chainntnfs/neutrinonotify"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/kvdb"
@@ -63,6 +64,10 @@ type Config struct {
 	// state.
 	ChanStateDB *channeldb.ChannelStateDB
 
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
+
 	// BlockCache is the main cache for storing block information.
 	BlockCache *blockcache.BlockCache