重构组件，优化性能并移除不必要的属性；撤销滚动条修改；

src/components/chat/AgentWorkspace.tsx

@@ -23,8 +23,6 @@ type AgentWorkspaceProps = {
   branchGroups: BranchGroup[];
   branchTransition: BranchTransition | null;
   isStreaming: boolean;
-  scrollContainerRef: React.RefObject<HTMLDivElement | null>;
-  onScroll: React.UIEventHandler<HTMLDivElement>;
   bottomRef: React.RefObject<HTMLDivElement | null>;
   speakingMessageId: string | null;
   speechState: SpeechState;
@@ -157,8 +155,6 @@ export const AgentWorkspace = ({
   branchGroups,
   branchTransition,
   isStreaming,
-  scrollContainerRef,
-  onScroll,
   bottomRef,
   speakingMessageId,
   speechState,
@@ -220,8 +216,6 @@ export const AgentWorkspace = ({
 
   return (
     <Box
-      ref={scrollContainerRef}
-      onScroll={onScroll}
       sx={{
         flex: 1,
         overflowY: "auto",