Reserve or unreserve a visionary slot

curl --request POST \
  --url https://api.fluxer.app/v1/admin/visionary-slots/reserve \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "slot_index": 1073741824,
  "user_id": "<string>"
}
'

{
  "success": true
}