lnrpc: add new StaticRemoteKey field to ListChannels output

lnrpc/rpc.proto

@@ -1237,6 +1237,14 @@ message Channel {
     The minimum satoshis the other node is required to reserve in its balance.
     */
     int64 remote_chan_reserve_sat = 21 [json_name = "remote_chan_reserve_sat"];
+
+    /**
+    If true, then this channel uses the modern commitment format where the key
+    in the output of the remote party does not change each state. This makes
+    back up and recovery easier as when the channel is closed, the funds go
+    directly to that key. 
+    */
+    bool static_remote_key = 22 [json_name = "static_remote_key"];
 }
 
 

lnrpc/rpc.swagger.json

@@ -1654,6 +1654,11 @@
           "type": "string",
           "format": "int64",
           "description": "*\nThe minimum satoshis the other node is required to reserve in its balance."
+        },
+        "static_remote_key": {
+          "type": "boolean",
+          "format": "boolean",
+          "description": "*\nIf true, then this channel uses the modern commitment format where the key\nin the output of the remote party does not change each state. This makes\nback up and recovery easier as when the channel is closed, the funds go\ndirectly to that key."
         }
       }
     },

rpcserver.go

@@ -2684,6 +2684,7 @@ func createRPCOpenChannel(r *rpcServer, graph *channeldb.ChannelGraph,
 		ChanStatusFlags:       dbChannel.ChanStatus().String(),
 		LocalChanReserveSat:   int64(dbChannel.LocalChanCfg.ChanReserve),
 		RemoteChanReserveSat:  int64(dbChannel.RemoteChanCfg.ChanReserve),
+		StaticRemoteKey:       dbChannel.ChanType.IsTweakless(),
 	}
 
 	for i, htlc := range localCommit.Htlcs {