前端：

1、更新界面图标
2、修改消息缓存逻辑
3、新增清空未读消息数
后端：
1、修复不同时区导致的时间显示问题
2、新增清空未读消息数接口

frontend/web/src/stores/chat.js

@@ -10,8 +10,20 @@ export const useChatStore = defineStore('chat', {
         pageSize: 20
     }),
     actions: {
+        // 抽取统一的排序去重方法
+        pushAndSortMessages(newMsgs) {
+            const combined = [...this.messages, ...newMsgs];
+            // 1. 根据 msgId 或唯一 key 去重
+            const uniqueMap = new Map();
+            combined.forEach(m => uniqueMap.set(m.msgId || m.id, m));
+
+            // 2. 转换为数组并按时间戳升序排序 (旧的在前，新的在后)
+            this.messages = Array.from(uniqueMap.values()).sort((a, b) => {
+                return new Date(a.timeStamp).getTime() - new Date(b.timeStamp).getTime();
+            });
+        },
         async addMessage(msg, sessionId) {
-            await messagesDb.save({ ...msg, sessionId });
+            await messagesDb.save({ ...msg, sessionId, isLoading: false });
             this.messages.push({ ...msg, sessionId })
         },
         /**
@@ -32,13 +44,13 @@ export const useChatStore = defineStore('chat', {
                 const serverHistoryMsg = await this.fetchHistoryFromServer(this.activeConversationId, conversation.lastReadMessageId);
                 //对消息进行过滤，防止重复消息
                 const filterMsg = serverHistoryMsg.filter(m => !this.messages.find(exist => exist.msgId === m.msgId));
-                this.messages = [...filterMsg, ...this.messages]
+                this.pushAndSortMessages([...filterMsg, ...this.messages]);
             }
             //拉取新消息
             this.fetchNewMsgFromServier(this.activeConversationId).then((newMsg) => {
                 //去重
                 const filterNewMsg = newMsg.filter(m => !this.messages.find(exist => exist.msgId === m.msgId));
-                this.messages = [...filterNewMsg, ...this.messages]
+                this.pushAndSortMessages([...filterNewMsg, ...this.messages])
             });
         },
         /**
@@ -88,7 +100,7 @@ export const useChatStore = defineStore('chat', {
             } else {
                 const fetchMsg = await this.fetchHistoryFromServer(this.conversationId, this.messages[0].msgId);
                 const newMsgs = fetchMsg.filter(m => !this.messages.find(exist => exist.msgId === m.msgId));
-                this.messages = [...newMsgs, ...this.messages]
+                this.pushAndSortMessages([...newMsgs, ...this.messages])
             }
         }
     }