feat: add custom edge (#1061)

### What problem does this PR solve?
feat: add custom edge
feat: add flow card
feat: add store for canvas
#918 

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

web/src/components/top-n-item.tsx

@@ -0,0 +1,23 @@
+import { useTranslate } from '@/hooks/commonHooks';
+import { Form, Slider } from 'antd';
+
+type FieldType = {
+  top_n?: number;
+};
+
+const TopNItem = () => {
+  const { t } = useTranslate('chat');
+
+  return (
+    <Form.Item<FieldType>
+      label={t('topN')}
+      name={'top_n'}
+      initialValue={8}
+      tooltip={t('topNTip')}
+    >
+      <Slider max={30} />
+    </Form.Item>
+  );
+};
+
+export default TopNItem;