Sign in with Stacks

[pradel]

Add Sign in with Stacks similar to https://github.com/spruceid/siwe to micro-stacks following the SIP specification stacksgov/sips#70

[aulneau]

I have an initial version implemented: https://github.com/fungible-systems/micro-stacks/blob/main/packages/client/src/micro-stacks-client.ts#L412

[pradel]

Really cool 👍