mod: show fullscreen action item

Closes #367

Signed-off-by: bggRGjQaUbCoE <githubaccount56556@proton.me>

lib/plugin/pl_player/controller.dart

@@ -254,6 +254,8 @@ class PlPlayerController {
   /// 弹幕开关
   Rx<bool> isOpenDanmu = false.obs;
 
+  late final showFSActionItem = GStorage.showFSActionItem;
+
   /// 弹幕权重
   int danmakuWeight = 0;
   int filterCount = 0;