fix: Cannot copy and paste text on agent page #3356 (#3357)

### What problem does this PR solve?

fix: Cannot copy and paste text on agent page #3356

### Type of change

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

web/src/pages/flow/hooks.ts

 import { FormInstance, message } from 'antd';
 import dayjs from 'dayjs';
 import { humanId } from 'human-id';
-import { lowerFirst } from 'lodash';
+import { get, lowerFirst } from 'lodash';
 import trim from 'lodash/trim';
 import { useTranslation } from 'react-i18next';
 import { useParams } from 'umi';
 
   const onCopyCapture = useCallback(
     (event: ClipboardEvent) => {
+      if (get(event, 'srcElement.tagName') !== 'BODY') return;
+
       event.preventDefault();
       const nodesStr = JSON.stringify(
         nodes.filter((n) => n.selected && n.data.label !== Operator.Begin),
 
   const onPasteCapture = useCallback(
     (event: ClipboardEvent) => {
-      event.preventDefault();
       const nodes = JSON.parse(
         event.clipboardData?.getData('agent:nodes') || '[]',
       ) as Node[] | undefined;
-      if (nodes) {
+
+      if (Array.isArray(nodes) && nodes.length) {
+        event.preventDefault();
         nodes.forEach((n) => {
           duplicateNode(n.id, n.data.label);
         });