gnocrux - a threshold TM2 signer

[zivkovicmilos]

Description

This issue proposes the creation of gnocrux, a threshold signing system inspired by horcrux.

Different to horcrux, gnocrux should utilize a consensus system based on Tendermint, using the libtm consensus engine developed for TM2.

Signer nodes can communicate directly though gRPC, and can even utilize libp2p if need be, for more robust networking operations (pubsub). We have a p2p package build exclusively for these sorts of scenarios: p2p.

We utilize ed25519 keys for validator block / message signing in gno / TM2.

Outstanding scope of work:

• Validate and implement missing pieces of the existing Tendermint2 remote signer mechanism
• Implement key splitting for ed25519 keys, that can be used by signer instances
• Define, and implement a bootstrap process for gnocrux signers, that converge on the committed signature through consensus

cc @r3v4s @mazzy89 @sw360cab @albttx @aeddi