Admin Clean Eventdescr

Manually trigger description cleanup (dev/testing endpoint).

Deletes event_description fields older than 72 hours to comply with GDPR data minimization principles.

NOTE: This endpoint is for development and testing only. In production, cleanup runs automatically via Celery every 6 hours.

Protection will be added later.

Returns: { "success": True, "data": { "descriptions_deleted": int, "message": str } }