refactor(llm): 调整流式聊天的超时时间

- 将 SseEmitter 的超时时间从 60_000 毫秒调整为 120_000 毫秒
-这样可以提供更长的响应时间，避免因超时导致的连接中断

yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/controller/admin/conversation/ConversationController.java

@@ -110,7 +110,7 @@ public class ConversationController {
     @PostMapping("/stream-chat")
     public SseEmitter streamChat (@Valid @RequestBody ChatReqVO chatReqVO, HttpServletResponse response) {
         log.info("收到对话推理请求，请求参数: {}", chatReqVO);
-        SseEmitter emitter = new SseEmitter(60_000L);
+        SseEmitter emitter = new SseEmitter(120_000L);
         ExecutorService executor = Executors.newSingleThreadExecutor();
         try {
             executor.execute(() -> {