feat: Authentication using SIWE on multiple chains.

[richtera]

What is the feature you would like to implement?
Since SIWE authentication lets you cryptographically prove the user has an address or abstracted account, it looks interesting whether this kind of signature could be used for a user to login using wagmi.

Why is this feature important?
Currently it's possible to verify other addresses on other chains inside of farcaster; this might make it possible to in addition use those verified addresses to login to farcaster.

Will the protocol spec need to be updated??
I don't think so since it's a normal SIWE packet just on another chain, which would also need to have a registered RPC provider, but probably not much more.

How should this feature be built? (optional)
Initially it might be useful to prepare a hubble fork running being able to connect with other chains in addition to the current list.