debug: 修复时序问题导致的获取会话列表为空的问题

src/services/conversationApi.ts

@@ -115,6 +115,23 @@ export const conversationApi = {
    */
   async fetchConversations(): Promise<Conversation[]> {
     const authStore = useAuthStore();
+    // 等待 authStore 初始化完成                                   
+    if (!authStore.isInitialized) {                                
+      await new Promise<void>((resolve) => {                       
+        const unwatch = authStore.$subscribe(() => {               
+          if (authStore.isInitialized) {                           
+            unwatch();                                             
+            resolve();                                             
+          }                                                        
+        });                                                        
+        // 如果已经初始化了，立即 resolve                          
+        if (authStore.isInitialized) {                             
+          unwatch();                                               
+          resolve();                                               
+        }                                                          
+      });                                                          
+    }                                                              
+              
     const userId = authStore.userId;
 
     // 构建 URL，添加 user_id 查询参数