Implement Nova's Offchain-Decider circuits

[arnaucube]

• Implement Nova's Offchain-Decider circuits (on both curves) (curve1 circuit: ~152k constraints, curve2 circuit: ~8k constraints) following the enumeration of the Offchain Decider docs: https://privacy-scaling-explorations.github.io/sonobe-docs/design/nova-decider-offchain.html
• Update enumeration of checks in Onchain-Decider circuit (decider_eth_circuit.rs) to match the updated Onchain Decider docs: https://privacy-scaling-explorations.github.io/sonobe-docs/design/nova-decider-onchain.html

[arnaucube]

(rebased to latest main branch changes)

[arnaucube]

Regarding

Also, this is inline with a question that I have. Don't we need to check the equality of anything between the two proofs? I mention this since if we don't check the consistency(and relation) between the two curve proofs, then we can easily get into trouble.

Yes, plus checking the commitments and other checks that the decider needs to do (more details at the "Outside the circuits" section of the offchain-decider docs). This is done at the Decider's verifier, but this PR focuses on the circuits implementation (that's why the title of the PR and name of the branch).