feat: overloaded RpcResult.result() waits a msgpack nil result

feat: RpcResult destructor invokes .result()

Author: eigen-value

src/bridge.h

@@ -60,11 +60,19 @@ class RpcResult {
         return error.code == NO_ERR;
     }
 
-    operator bool() {
+    bool result() {
         MsgPack::object::nil_t nil;
         return result(nil);
     }
 
+    ~RpcResult(){
+        result();
+    }
+
+    operator bool() {
+        return result();
+    }
+
 private:
     uint32_t msg_id_wait;
     RPCClient* client;