channeldb+lnwallet: save initial balances during channel opening

lnwallet/reservation.go

@@ -403,8 +403,10 @@ func NewChannelReservation(capacity, localFundingAmt btcutil.Amount,
 				FeePerKw:      btcutil.Amount(commitFeePerKw),
 				CommitFee:     commitFee,
 			},
-			ThawHeight: thawHeight,
-			Db:         wallet.Cfg.Database,
+			ThawHeight:           thawHeight,
+			Db:                   wallet.Cfg.Database,
+			InitialLocalBalance:  ourBalance,
+			InitialRemoteBalance: theirBalance,
 		},
 		pushMSat:      pushMSat,
 		pendingChanID: pendingChanID,