Simulate - return fees used information

follow-up to #3953.

When using simulate, the dev should be able to get a response of how many min fees were used to execute the transaction group.

In other words: report # of transactions and "fee credit". This should automatically be reported from any simulate call.

This story is only for reporting - devs can execute with effectively unlimited fees by sending a large amount of Algos along with the transaction (since this is simulate, the Algos won't be truly consumed).