Create a signed transform URL

curl --request POST \
  --url https://convertly.sh/api/media/signed-transform \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "sourceUrl": "<string>"
}
'

{
  "url": "<string>",
  "expiresAt": "2023-11-07T05:31:56Z"
}