Feat: Convert the prompt field of the agent operator to an array #3221 (#8137)

### What problem does this PR solve?

Feat: Convert the prompt field of the agent operator to an array #3221

### Type of change


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

web/src/pages/agent/chat/hooks.ts

@@ -14,10 +14,13 @@ import { Message } from '@/interfaces/database/chat';
 import i18n from '@/locales/config';
 import api from '@/utils/api';
 import { message } from 'antd';
+import { get } from 'lodash';
 import trim from 'lodash/trim';
-import { useCallback, useEffect } from 'react';
+import { useCallback, useEffect, useMemo } from 'react';
 import { useParams } from 'umi';
 import { v4 as uuid } from 'uuid';
+import { BeginId } from '../constant';
+import useGraphStore from '../store';
 import { receiveMessageError } from '../utils';
 
 const antMessage = message;
@@ -56,6 +59,17 @@ function findMessageFromList(eventList: IEventList) {
   return event?.data?.content;
 }
 
+const useGetBeginNodePrologue = () => {
+  const getNode = useGraphStore((state) => state.getNode);
+
+  return useMemo(() => {
+    const formData = get(getNode(BeginId), 'data.form', {});
+    if (formData?.enablePrologue) {
+      return formData?.prologue;
+    }
+  }, [getNode]);
+};
+
 export const useSendNextMessage = () => {
   const {
     reference,
@@ -75,6 +89,8 @@ export const useSendNextMessage = () => {
     api.runCanvas,
   );
 
+  const prologue = useGetBeginNodePrologue();
+
   const sendMessage = useCallback(
     async ({ message }: { message: Message; messages?: Message[] }) => {
       const params: Record<string, unknown> = {
@@ -138,19 +154,18 @@ export const useSendNextMessage = () => {
     });
   }, [addNewestQuestion, handleSendMessage, done, setValue, value]);
 
-  const fetchPrologue = useCallback(async () => {
-    // fetch prologue
-    const sendRet = await send({ id: agentId });
-    if (receiveMessageError(sendRet)) {
-      message.error(sendRet?.data?.message);
-    } else {
-      refetch();
-    }
-  }, [agentId, refetch, send]);
-
   useEffect(() => {
-    fetchPrologue();
-  }, [fetchPrologue]);
+    if (prologue) {
+      addNewestAnswer({
+        answer: prologue,
+        reference: {
+          chunks: [],
+          doc_aggs: [],
+          total: 0,
+        },
+      });
+    }
+  }, [addNewestAnswer, prologue]);
 
   return {
     handlePressEnter,