refactor: battle at controller

internal/game/controller_test.go

@@ -46,7 +46,7 @@ func g(t *testing.T, f func(p func(*controller.Param), g func() *mg.Game)) {
 		g, err := game.LoadState(p)
 		if err != nil {
 			assert.FailNow(t, "g: LoadState", err)
-			return nil // mg.Game{}
+			return nil
 		}
 		return g
 	}