opt: nextPlay logic & style

lib/pages/later/controller.dart

@@ -122,6 +122,7 @@ class LaterController extends GetxController {
         'heroTag': heroTag,
         'sourceType': 'watchLater',
         'count': laterList.length,
+        'mediaId': userInfo!.mid,
       },
     );
   }

lib/pages/video/detail/introduction/controller.dart

@@ -523,7 +523,7 @@ class VideoIntroController extends GetxController {
         Get.find<VideoDetailController>(tag: heroTag);
 
     /// 优先稍后再看、收藏夹
-    if (videoDetailCtr.isWatchLaterVisible.value) {
+    if (videoDetailCtr.sourceType.value != 'normal') {
       episodes.addAll(videoDetailCtr.mediaList);
     } else if (videoDetail.value.ugcSeason != null) {
       final UgcSeason ugcSeason = videoDetail.value.ugcSeason!;

lib/pages/video/detail/widgets/watch_later_list.dart

@@ -85,10 +85,13 @@ class _MediaListPanelState extends State<MediaListPanel> {
           AppBar(
             toolbarHeight: 45,
             automaticallyImplyLeading: false,
-            title: Text(
+            title: Padding(
+              padding: const EdgeInsets.only(left: 12),
+              child: Text(
                 widget.panelTitle ?? '稍后再看',
                 style: Theme.of(context).textTheme.titleSmall,
               ),
+            ),
             actions: [
               IconButton(
                 icon: const Icon(Icons.close, size: 20),