fix(slack): allow subject.id to be a number

src/dispatch/plugins/dispatch_slack/models.py

@@ -1,7 +1,7 @@
 """Models for Slack command payloads in the Dispatch application."""
 
 from typing import TypedDict, NewType
-from pydantic import BaseModel, AnyHttpUrl
+from pydantic import BaseModel, AnyHttpUrl, ConfigDict
 import logging
 from dispatch.enums import DispatchEnum
 
@@ -37,6 +37,10 @@ class SubjectMetadata(BaseModel):
     channel_id: str | None = None
     thread_id: str | None = None
 
+    model_config = ConfigDict(
+        coerce_numbers_to_str=True
+    )  # allow coercion of id from number to string
+
 
 class AddUserMetadata(SubjectMetadata):
     """Model for metadata when adding users."""