feat(infrastructure): use celery worker

backend/app/workers/celery_tasks.py

@@ -1,5 +1,4 @@
 import logging
-from typing import Any, Dict
 
 from celery import shared_task
 
@@ -11,34 +10,10 @@ logger.setLevel(logging.INFO)
 
 
 @shared_task(name="workers.send_email")
-def send_email(payload: Dict[str, Any]) -> None:
-    """Celery task to send an email.
-
-    Expected payload schema:
-    {
-        "type": "email",
-        "to": "recipient@example.com",
-        "subject": "Subject text",
-        "body": "Email body text"
-    }
-
-    This mirrors the previous queue worker contract to minimize changes upstream.
-    """
-    to = payload.get("to")
-    subject = payload.get("subject")
-    body = payload.get("body")
+def send_email(to: str, subject: str, body: str) -> None:
     if not (to and subject and body):
-        logger.error("Email task missing fields. Payload: %s", payload)
+        logger.error("Email task missing fields. to=%r subject=%r body_len=%r", to, subject, len(body) if body else 0)
         return
 
     # Placeholder for real email sending logic
-    # Implement SMTP provider call here
     logger.info("[Celery] Email sent | to=%s | subject=%s | body_len=%d", to, subject, len(body))
-
-
-@shared_task(name="workers.send_email_fields")
-def send_email_fields(to: str, subject: str, body: str) -> None:
-    """Alternate signature for convenience when calling from app code.
-    Routes to the same implementation as send_email.
-    """
-    send_email({"type": "email", "to": to, "subject": subject, "body": body})