* add dbx queries
* add migration file
* start service
* Add TotalReferredCountByUserId and availableCreditsByUserID
* implement UserCredits interface and UserCredit struct type
* add UserCredits into consoledb
* add setupData helper function
* add test for update
* update lock file
* fix lint error
* add invalidUserCredits tests
* rename method
* adds comments
* add checks for erros in setupData
* change update method to only execute one query per request
* rename vairable
* should return a signal from Update method if the charge is not fully complete
* changes for readability
* prevent sql injection
* rename
* improve readability
