Proposal: modify nargo to support third party plugins like cargo

[Ethan-000]

Problem

Support third party plugins so nargo functionalities can be extended by the community without requiring the nargo team to maintain everything

more on this here https://github.com/rust-lang/cargo/wiki/Third-party-cargo-subcommands

related to #2164 but should be more general

Happy Case

users can run something like nargo halo2 prove

Alternatives Considered

No response

Additional Context

No response

Would you like to submit a PR for this Issue?

Maybe

Support Needs

No response

[Savio-Sou]

@TomAFrench any thoughts on approaching #2164 via this method?

[kevaundray]

If this is the way we want to move forward long term, we should go for this after having an MVP of dynamic backends since dynamic backends is a blocker for us moving to barretenberg master and using the release artifacts from barretenberg

[TomAFrench]

Yeah, changing to a generic plugin model would be a massive scope creep.

[Savio-Sou]

Makes sense, thanks for the clarifications!

[Savio-Sou]

Note that for integrating halo2 / proving backend specifically, we now have nargo backend that supports installation and switching between backends.