fix: knowledge bases under existing 知识库管理 menu

src/App.tsx

@@ -71,7 +71,7 @@ function App() {
                       </PermissionGuard>
                     }
                   />
-                  <Route path="knowledge/bases" element={<Placeholder title="知识库列表" />} />
+                  <Route path="knowledge/bases" element={<Suspense fallback={<PageLoading />}><KnowledgeBasesPage /></Suspense>} />
                   <Route path="knowledge/sources" element={<Placeholder title="知识源列表" />} />
                   <Route path="imports" element={<Placeholder title="文档导入" />} />
                   <Route path="files" element={<Placeholder title="文件与 COS" />} />

src/config/menu.tsx

@@ -44,7 +44,6 @@ export const adminMenuItems: AdminMenuItem[] = [
   { path: '/imports', name: '文档导入', icon: <ImportOutlined /> },
   { path: '/files', name: '文件与 COS', icon: <FileOutlined /> },
   { path: '/settings', name: '系统配置', icon: <SettingOutlined />, requiredRole: 'ADMIN' },
-  { path: '/knowledge/bases', name: '知识库列表', icon: <BookOutlined /> },
   { path: '/billing', name: 'API 用量', icon: <DollarOutlined />, requiredRole: 'SUPER_ADMIN' },
   { path: '/git', name: '代码仓库', icon: <CodeOutlined /> },
   { path: '/servers', name: '服务器运维', icon: <CloudServerOutlined />, requiredRole: 'SUPER_ADMIN' },