remove all sysvar pubkeys from instructions interface

[2501babe]

because of syscalls, we do not need to pass in any sysvar accounts. we can also get rid of stake config entirely. to preserve the interface for past transactions, we can skip the relevant accounts in a wrapper on next_account_info()

this should (in the case of clock and rent) and absolutely will greatly (in the case of stake history) reduce CU usage because these accounts do not need to be parsed into AccountInfos. it will also make transactions that use stake account instructions typically 32-128 bytes smaller

this was not done for the initial version on purpose because above all else except correctness, we prioritized following the native stake program as closely as possible, to de-risk the native/bpf switchover. but this is probably the first pr i will land after launch