feat: bytecode hashing init

[IlyasRidhuan]

This adds proper computation of the public bytecode commitment (i.e. pair-wise poseidon hashing of the public bytecode). This hash is also computed in the witgen although the circuit remains unconstrained.

Follow up PRs will handle:

1. Deriving class id, including tracing and hinting the artifact hash, etc
2. Deriving the address, including tracing and hinting the contract instance
3. Merkle path hinting and verification in the AVM