Feat: Use shadcn-ui to build GenerateForm. #3221 (#5449)

### What problem does this PR solve?

Feat: Use shadcn-ui to build GenerateForm. #3221

### Type of change


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

web/src/pages/agent/form-sheet/next.tsx

@@ -122,7 +122,7 @@ const FormSheet = ({
             <span>{t(`${lowerFirst(operatorName)}Description`)}</span>
           </section>
         </SheetHeader>
-        <section>
+        <section className="pt-4">
           {visible && (
             <FlowFormContext.Provider value={node}>
               <OperatorForm

web/src/pages/agent/form-sheet/use-form-config-map.tsx

@@ -82,8 +82,15 @@ export function useFormConfigMap() {
     },
     [Operator.Generate]: {
       component: GenerateForm,
-      defaultValues: {},
-      schema: z.object({}),
+      defaultValues: {
+        cite: true,
+        prompt: t('flow.promptText'),
+      },
+      schema: z.object({
+        prompt: z.string().min(1, {
+          message: t('flow.promptMessage'),
+        }),
+      }),
     },
     [Operator.Answer]: {
       component: AnswerForm,