fix: relax email validation for .local domains in agent notify endpoint

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend-compliance/compliance/api/agent_notification_routes.py

@@ -9,7 +9,7 @@ import logging
 from datetime import datetime, timezone
 
 from fastapi import APIRouter
-from pydantic import BaseModel, EmailStr
+from pydantic import BaseModel
 
 from compliance.services.smtp_sender import send_email
 
@@ -19,7 +19,7 @@ router = APIRouter(prefix="/compliance/agent", tags=["agent"])
 
 
 class NotifyRequest(BaseModel):
-    recipient: EmailStr
+    recipient: str
     subject: str
     body_html: str
     role: str