meta embed fixes

backend/app/whatsapp_onboarding.py

@@ -49,6 +49,7 @@ def signup_public_config(db: Session) -> dict[str, Any]:
         "app_id": app_id or None,
         "config_id": config_id or None,
         "api_version": settings.whatsapp_api_version,
+        "sdk_version": "v26.0",
         "ready": bool(app_id and config_id and secret),
     }