fix: Design glitches in sticker dialog

lib/pages/chat/sticker_picker_dialog.dart

@@ -73,7 +73,9 @@ class StickerPickerDialogState extends State<StickerPickerDialog> {
             physics: const NeverScrollableScrollPhysics(),
             itemBuilder: (BuildContext context, int imageIndex) {
               final image = pack.images[imageKeys[imageIndex]]!;
-              return InkWell(
+              return Tooltip(
+                message: image.body ?? imageKeys[imageIndex],
+                child: InkWell(
                   radius: AppConfig.borderRadius,
                   key: ValueKey(image.url.toString()),
                   onTap: () {
@@ -95,6 +97,7 @@ class StickerPickerDialogState extends State<StickerPickerDialog> {
                       isThumbnail: false,
                     ),
                   ),
+                ),
               );
             },
           ),
@@ -111,6 +114,7 @@ class StickerPickerDialogState extends State<StickerPickerDialog> {
             SliverAppBar(
               floating: true,
               pinned: true,
+              scrolledUnderElevation: 0,
               automaticallyImplyLeading: false,
               backgroundColor: Colors.transparent,
               title: SizedBox(
@@ -118,6 +122,7 @@ class StickerPickerDialogState extends State<StickerPickerDialog> {
                 child: TextField(
                   autofocus: false,
                   decoration: InputDecoration(
+                    filled: true,
                     hintText: L10n.of(context).search,
                     prefixIcon: const Icon(Icons.search_outlined),
                     contentPadding: EdgeInsets.zero,