Bulk update user flags

curl --request POST \
  --url https://api.fluxer.app/v1/admin/bulk/update-user-flags \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "user_ids": [
    "<string>"
  ],
  "add_flags": [
    "<string>"
  ],
  "remove_flags": [
    "<string>"
  ]
}
'

{
  "successful": [
    "<string>"
  ],
  "failed": [
    {
      "id": "<string>",
      "error": "<string>"
    }
  ]
}