curl --request POST \
  --url http://localhost:3000/v1/admin/partners/payouts/{partnerId}/mark-paid \
  --header 'Content-Type: application/json' \
  --data '
{
  "period": "2026-01",
  "notes": "<string>"
}
'

{
  "success": true,
  "updated_count": 123,
  "amount_paid": 123,
  "message": "<string>"
}