Copy solana-stake-interface into this repo

[kevinheavey]

This is one possible solution to the problem in #4529

We would publish this in the 2.2.0 release, and then by 2.3.0 we'd want to have solana-sysvar-id moved out of the repo so we can go back to using the stake-interface crate at https://github.com/solana-program/stake/tree/main/interface.

We would then remove this copy from the monorepo

[mergify]

The Firedancer team maintains a line-for-line reimplementation of the
native programs, and until native programs are moved to BPF, those
implementations must exactly match their Agave counterparts.
If this PR represents a change to a native program implementation (not
tests), please include a reviewer from the Firedancer team. And please
keep refactors to a minimum.

[kevinheavey]

Closed by #4664