Improved ip-lookup endpoint & credit docs

We have released a small update to the ip-lookup endpoint. You can now see the credit status as part of the header data and we added the option to set a dataset ID, allowing you to track how credits are consumed across multiple sites or clients.
https://developers.leadboxer.com/reference/lookupip

We also updated our credit definitions, and how or when we deduct credits.
https://developers.leadboxer.com/docs/credit-usage-cost-model