ExpectParamGet is a helper function that sets up an expected mock call for the provided type.

GetBalance gets the balance from the account, returning a default, zero value balance if no balance is found.

GetCreditTypeFromBatchDenom extracts the classId from a batch denom string, then retrieves it from the params.

GetNonNegativeFixedDecs takes an arbitrary amount of decimal strings, and returns their corresponding fixed decimals in a slice.