[new]聊天界面增加回弹效果

lib/module/chat/view.dart

@@ -144,6 +144,8 @@ class ChatPage extends BasePage<ChatController> {
                 onRefresh: controller.loadMoreHistory,
                 child: ListView.builder(
                     reverse: true,
+                    physics: const BouncingScrollPhysics(
+                        parent: AlwaysScrollableScrollPhysics()),
                     controller: controller.listScrollController,
                     itemBuilder: _chatItemBuilder,
                     itemCount: controller.chatItems.length),