lnrpc: add features field to invoices

lnrpc/rpc.proto

@@ -2371,6 +2371,9 @@ message Invoice {
 
     /// List of HTLCs paying to this invoice [EXPERIMENTAL].
     repeated InvoiceHTLC htlcs = 22 [json_name = "htlcs"];
+
+    /// List of features advertised on the invoice.
+    repeated Feature features = 24 [json_name = "features"];
 }
 
 enum InvoiceHTLCState {

lnrpc/rpc.swagger.json

@@ -2802,6 +2802,13 @@
             "$ref": "#/definitions/lnrpcInvoiceHTLC"
           },
           "description": "/ List of HTLCs paying to this invoice [EXPERIMENTAL]."
+        },
+        "features": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/lnrpcFeature"
+          },
+          "description": "/ List of features advertised on the invoice."
         }
       }
     },