curl --request POST \
  --url https://app.teable.ai/api/chat/onboarding/attachments \
  --header 'Authorization: Bearer REPLACE_BEARER_TOKEN' \
  --header 'content-type: application/json' \
  --data '{"tokens":["string"]}'

{
  "attachments": [
    {
      "token": "<string>",
      "name": "<string>",
      "path": "<string>",
      "mimetype": "<string>",
      "size": 123,
      "presignedUrl": "<string>"
    }
  ]
}