Local poseidon crate from mina-rust consolidated into proof-systems

[dannywillems]

Summary

Consolidate the local poseidon/ crate from mina-rust into proof-systems/mina-poseidon, eliminating code duplication and providing Mina-specific functionality to all proof-systems consumers.

Background

The mina-rust repository contains a local poseidon/ crate that duplicates and extends functionality from proof-systems/mina-poseidon. This crate includes Mina-specific:

• Hash parameter definitions (50+ lazy static params: MINA_ACCOUNT, MINA_PROTO_STATE, MINA_MERKLE_TREE_*, etc.)
• Inputs builder for constructing hash inputs with packed fields
• LazyParam for pre-computed sponge states
• Legacy sponge support (PlonkSpongeConstantsLegacy)

Current usage

The local poseidon crate is used by 32 files across:

• ledger/ (proofs, scan_state, accounts, verification)
• snark/
• vrf/
• p2p-messages/
• node/
• core/

Related

• Investigation: Investigate if Poseidon subcrate should live in OpenMina or proof-systems #1215

• proof-systems had to be updated to 1.91/1.92. It has been tracked here.

• This is a blocker for zkApp command signing implementation #1768.