fix：When creating a new assistant, an avatar was uploaded, but when selecting the assistant to start a new chat, the default avatar still appears in the chat window instead of the one uploaded during creation (#7769)

### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [ ] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [ ] Refactoring
- [ ] Performance Improvement
- [ ] Other (please describe):

web/src/pages/chat/chat-container/index.tsx

 import {
   useFetchNextConversation,
   useGetChatSearchParams,
+  useFetchNextDialog,
 } from '@/hooks/chat-hooks';
 import { useFetchUserInfo } from '@/hooks/user-setting-hooks';
 import { buildMessageUuidWithRole } from '@/utils/chat';
 const ChatContainer = ({ controller }: IProps) => {
   const { conversationId } = useGetChatSearchParams();
   const { data: conversation } = useFetchNextConversation();
+  const { data: currentDialog } = useFetchNextDialog();
+    
 
   const {
     value,
                     item={message}
                     nickname={userInfo.nickname}
                     avatar={userInfo.avatar}
-                    avatarDialog={conversation.avatar}
+                    avatarDialog={currentDialog.icon}
                     reference={buildMessageItemReference(
                       {
                         message: derivedMessages,