feat: make prompt object type array in pipeline config

pkg/platform/sources/qqbotpy.yaml

@@ -28,9 +28,11 @@ spec:
       label:
         en_US: Intents
         zh_CN: 权限
-      type: array[string]
+      type: array
       required: true
       default: []
+      items:
+        type: string
 execution:
   python:
     path: ./qqbotpy.py

templates/metadata/pipeline/ai.yaml

@@ -54,9 +54,16 @@ stages:
         label:
           en_US: Prompt
           zh_CN: 提示词
-        type: string
+        type: array
         required: true
-        default: "You are a helpful assistant."
+        items:
+          type: object
+          properties:
+            role:
+              type: string
+              default: user
+            content:
+              type: string
   - name: dify-service-api
     label:
       en_US: Dify Service API