处理滚动底部问题

keyBoard/Class/AiTalk/V/Chat/KBPersonaChatCell.m

@@ -453,8 +453,43 @@ static NSString * const KBChatSessionDidResetNotification = @"KBChatSessionDidRe
     [self.chatView addMessage:message autoScroll:YES];
 }
 
+- (void)appendLoadingUserMessage {
+    if (!self.messages) {
+        self.messages = [NSMutableArray array];
+    }
+    
+    [self ensureOpeningMessageAtTop];
+    KBAiChatMessage *message = [KBAiChatMessage loadingUserMessage];
+    [self.messages addObject:message];
+    [self.chatView addMessage:message autoScroll:YES];
+}
+
+- (void)updateLastUserMessage:(NSString *)text {
+    [self.chatView updateLastUserMessage:text];
+    
+    // 更新数据源中的消息
+    for (NSInteger i = self.messages.count - 1; i >= 0; i--) {
+        KBAiChatMessage *message = self.messages[i];
+        if (message.type == KBAiChatMessageTypeUser && message.isLoading) {
+            message.text = text;
+            message.isLoading = NO;
+            message.isComplete = YES;
+            break;
+        }
+    }
+}
+
 - (void)markLastUserMessageLoadingComplete {
-//    [self.chatView markLastUserMessageLoadingComplete];
+    [self.chatView markLastUserMessageLoadingComplete];
+
+    // 同步更新数据源
+    for (NSInteger i = self.messages.count - 1; i >= 0; i--) {
+        KBAiChatMessage *message = self.messages[i];
+        if (message.type == KBAiChatMessageTypeUser && message.isLoading) {
+            message.isLoading = NO;
+            break;
+        }
+    }
 }
 
 - (void)appendAssistantMessage:(NSString *)text