feat: n to 1 retrieval legacy (#6554)

web/app/components/workflow/nodes/knowledge-retrieval/hooks.ts

@@ -0,0 +1,14 @@
+import { useMemo } from 'react'
+import { getSelectedDatasetsMode } from './utils'
+import type {
+  DataSet,
+  SelectedDatasetsMode,
+} from '@/models/datasets'
+
+export const useSelectedDatasetsMode = (datasets: DataSet[]) => {
+  const selectedDatasetsMode: SelectedDatasetsMode = useMemo(() => {
+    return getSelectedDatasetsMode(datasets)
+  }, [datasets])
+
+  return selectedDatasetsMode
+}