Feat: Construct RetrievalForm with original fields #3221 (#8012)

### What problem does this PR solve?

Feat: Construct RetrievalForm with original fields #3221

### Type of change


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

web/src/pages/agent/form/components/query-variable.tsx

@@ -0,0 +1,31 @@
+import { SelectWithSearch } from '@/components/originui/select-with-search';
+import {
+  FormControl,
+  FormField,
+  FormItem,
+  FormLabel,
+  FormMessage,
+} from '@/components/ui/form';
+import { useFormContext } from 'react-hook-form';
+import { useTranslation } from 'react-i18next';
+
+export function QueryVariable() {
+  const { t } = useTranslation();
+  const form = useFormContext();
+
+  return (
+    <FormField
+      control={form.control}
+      name="query"
+      render={({ field }) => (
+        <FormItem>
+          <FormLabel tooltip={t('chat.modelTip')}>{t('flow.query')}</FormLabel>
+          <FormControl>
+            <SelectWithSearch {...field}></SelectWithSearch>
+          </FormControl>
+          <FormMessage />
+        </FormItem>
+      )}
+    />
+  );
+}