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/form/agent-form/dynamic-prompt.tsx

@@ -12,11 +12,7 @@ import { memo } from 'react';
 import { useFieldArray, useFormContext } from 'react-hook-form';
 import { useTranslation } from 'react-i18next';
 import { PromptEditor } from '../components/prompt-editor';
-
-export enum PromptRole {
-  User = 'user',
-  Assistant = 'assistant',
-}
+import { PromptRole } from './constant';
 
 const options = [
   { label: 'User', value: PromptRole.User },