fix: remove Top K in retrieval testing #770 and if the document parsing fails, the error message returned by the backend is displayed (#782)

### What problem does this PR solve?

fix: remove Top K in retrieval testing  #770
fix: if the document parsing fails, the error message returned by the
backend is displayed.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/components/pdf-previewer/hooks.ts

@@ -0,0 +1,18 @@
+import axios from 'axios';
+import { useCallback, useEffect, useState } from 'react';
+
+export const useCatchDocumentError = (url: string) => {
+  const [error, setError] = useState<string>('');
+
+  const fetchDocument = useCallback(async () => {
+    const { data } = await axios.get(url);
+    if (data.retcode !== 0) {
+      setError(data?.retmsg);
+    }
+  }, [url]);
+  useEffect(() => {
+    fetchDocument();
+  }, [fetchDocument]);
+
+  return error;
+};