testbed: input command NONE

testbed/component/input_listener_component.h

@@ -4,13 +4,14 @@ namespace testbed {
 
 struct input_listener_component {
     enum class type {
+        NONE,
         UP,
         DOWN,
         LEFT,
         RIGHT
     };
 
-    type command;
+    type command{type::NONE};
 };
 
 } // namespace testbed