[WIP]: vote-interface: explicitly use v3 everywhere

[buffalojoec]

Builds on the back of anza-xyz/solana-sdk#206.

Basically assumes we'd publish those changes in a new solana-vote-interface version, and demonstrates updating the dependency to Agave to use the new version.

Note we would explicitly use "v3" everywhere, which leaves the validator (and stake & vote program) functionally unchanged.

[mergify]

If this PR represents a change to the public RPC API:

1. Make sure it includes a complementary update to rpc-client/ (example)
2. Open a follow-up PR to update the JavaScript client @solana/kit (example)

Thank you for keeping the RPC clients in sync with the server API @buffalojoec.

[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.

[jstarry]

looks like the right direction to me! let's get those sdk changes in

[buffalojoec]

Closed in favor of #6987