Core BPF impl: Config

[buffalojoec]

This PR adds the Core BPF implementation of the Config program.

I think in general it makes sense to reduce dependency on the config program crate in the monorepo, so I've omitted the following for now:

• create_config_account (helper)
• impl ConfigState for StakeConfig

If that makes sense I'll look into refactoring over there.

Closes #2

[kevinheavey]

Re leaving create_config_account in the original config program crate, will that mean keeping the solana-config-program dependency in solana-account-decoder (this discussion) or is there some other plan for that?

[buffalojoec]

Re leaving create_config_account in the original config program crate, will that mean keeping the solana-config-program dependency in solana-account-decoder (this discussion) or is there some other plan for that?

Actually I was looking at refactoring config program out of the monorepo altogether, if possible. Wherever not possible, I think we can generate a client here and use just the client to supply account-decoder with the handlers it needs.

I think what might be best is to just move get_config_data and create_config_account into the client only, and not in the program anywhere. Wdyt?

[kevinheavey]

Wherever not possible, I think we can generate a client here and use just the client to supply account-decoder with the handlers it needs.

I don't think Kinobi generates any of what account-decoder needs for the config program: anza-xyz/agave#265 (comment)

So it will just be a matter of cut+paste from programs/config into the new client crate.

I think what might be best is to just move get_config_data and create_config_account into the client only, and not in the program anywhere. Wdyt?

Client seems like the right place to put them!

[buffalojoec]

I don't think Kinobi generates any of what account-decoder needs for the config program

You don't need to only rely on generated code for a generated client. There's code you can put client-side only.

[kevinheavey]

Oh sure I just meant that the generated code isn't anything to do with what account-decoder needs

[joncinque]

Great work! Mostly comments on the tests, but the program is perfect.

[joncinque]

One more program conversion for the books, great job!