fix(knowledge): 更新知识管理页面标题为知识集

- 将页面标题从"知识管理"修改为"知识集"

frontend/src/pages/KnowledgeManagement/Home/KnowledgeManagementPage.tsx

@@ -257,7 +257,7 @@ export default function KnowledgeManagementPage() {
   return (
     <div className="h-full flex flex-col gap-4">
       <div className="flex items-center justify-between">
-        <h1 className="text-xl font-bold">知识管理</h1>
+        <h1 className="text-xl font-bold">知识集</h1>
         <div className="flex gap-2 items-center">
           <Button onClick={() => navigate("/data/knowledge-management/search")}>
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