fix(knowledge): 修复知识集详情页面状态判断逻辑

- 修正了 office 预览状态的条件判断
- 移除了对 PENDING 状态的冗余检查
- 优化了状态轮询的触发条件

frontend/src/pages/KnowledgeManagement/Detail/KnowledgeSetDetail.tsx

@@ -400,7 +400,7 @@ const KnowledgeSetDetail = () => {
         if (currentStatus === "FAILED") {
           setOfficePreviewStatus("PROCESSING");
         }
-        if (currentStatus === "PROCESSING" || currentStatus === "PENDING") {
+        if (currentStatus === "PROCESSING") {
           pollOfficePreviewStatus(id, record.id, 0);
           return;
         }