feat(document-preview): add document preview page and improve chunk list UI

- Implement new document preview page with support for various file types
- Move file preview functionality from parsed-result to dedicated preview page
- Enhance chunk list UI with better visual hierarchy and styling
- Add document preview button in parsed-result page
- Improve error handling and loading states for both pages

src/routes/index.tsx

@@ -9,6 +9,7 @@ import { KnowledgeBaseList, KnowledgeBaseCreate, KnowledgeBaseDetail, KnowledgeB
 import MCP from '../pages/MCP';
 import FormFieldTest from '../pages/FormFieldTest';
 import ChunkParsedResult from '@/pages/chunk/parsed-result';
+import DocumentPreview from '@/pages/chunk/document-preview';
 
 const AppRoutes = () => {
   return (
@@ -38,6 +39,8 @@ const AppRoutes = () => {
       {/* 处理chunk相关路由 需要传入 kb_id doc_id */}
       <Route path="chunk">
         <Route path="parsed-result" element={<ChunkParsedResult />} />
+        {/* 文档预览页面路由 */}
+        <Route path="/document-preview/:kb_id/:doc_id" element={<DocumentPreview />} />
       </Route>
 
       {/* 处理未匹配的路由 */}