fix(player): 评论输入浮层补齐键盘区域实底

lib/pages/player/widgets/comment_composer_sheet.dart

@@ -137,22 +137,23 @@ class _CommentComposerSheetState extends State<CommentComposerSheet> {
         Positioned(
           left: 0,
           right: 0,
-          bottom: _pinnedKeyboardInset,
+          bottom: 0,
           child: GestureDetector(
             behavior: HitTestBehavior.opaque,
             onTap: () {},
-            child: SizedBox(
-              key: const Key('comment-composer-sheet'),
-              width: double.infinity,
-              child: Material(
-                color: AppColors.card,
-                clipBehavior: Clip.antiAlias,
-                borderRadius: const BorderRadius.vertical(
-                  top: Radius.circular(_sheetRadius),
-                ),
-                child: SafeArea(
-                  top: false,
+            child: Material(
+              key: const Key('comment-composer-panel'),
+              color: AppColors.card,
+              clipBehavior: Clip.antiAlias,
+              borderRadius: const BorderRadius.vertical(
+                top: Radius.circular(_sheetRadius),
+              ),
+              child: SafeArea(
+                top: false,
+                child: Padding(
+                  padding: EdgeInsets.only(bottom: _pinnedKeyboardInset),
                   child: Padding(
+                    key: const Key('comment-composer-sheet'),
                     padding: const EdgeInsets.fromLTRB(16, 12, 16, 12),
                     child: TextFieldTapRegion(
                       child: Column(