curl --request POST \
  --url https://app.teable.ai/api/base/%7BbaseId%7D/sign-attachment-urls \
  --header 'Authorization: Bearer REPLACE_BEARER_TOKEN' \
  --header 'content-type: application/json' \
  --data '{"attachments":[{"path":"string","token":"string","mimetype":"image/png"}]}'

{
  "attachments": [
    {
      "token": "<string>",
      "url": "<string>"
    }
  ]
}