feat: message-api for mission via wecomm agent

mission/models.py

@@ -6,6 +6,10 @@ from django.utils import timezone
 from flower.common import ModelBase
 
 
+class MissionPayloadProcessorEnum(models.TextChoices):
+    STRUCTURED_DESCRIPTION_V1 = "structured_description_v1", "结构化描述增强(v1)"
+
+
 class MissionCategory(ModelBase):
     """任务分类字典，按商户隔离。"""
 
@@ -17,6 +21,13 @@ class MissionCategory(ModelBase):
         verbose_name="所属商户",
     )
     name = models.CharField(max_length=50, verbose_name="分类名称")
+    payload_processor = models.CharField(
+        max_length=50,
+        blank=True,
+        default="",
+        choices=MissionPayloadProcessorEnum.choices,
+        verbose_name="payload 增强器",
+    )
 
     def __str__(self):
         return self.name