feat: Add verifyAndExecute external function to IIdentityManagerV2

[2PykeETH]

Summary

This PR introduces the verifyAndExecute external function to the IIdentityManagerV2 interface. This addition provides a standardized entry point for verifying user proofs and executing identity-related operations, ensuring seamless integration across contracts.

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Changes

• New External Function:

  • verifyAndExecute(...) added with the following parameters:
    • address signal: Input signal for proof verification.
    • uint256 root: Merkle root to validate inclusion proofs.
    • uint256 nullifierHash: Unique nullifier for replay protection.
    • uint256[8] calldata proof: zkSNARK proof array.
    • UserType userType: Enum indicating the classification of the user.
    • uint256 expirationTimestamp: Timestamp after which verification is invalid.

• NatSpec Documentation:

  • Clear section header and docstring to describe the function’s purpose and usage.

• Formatting:

  • Applied forge fmt for consistent Solidity code style.

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Motivation

• Establish a consistent verification flow across all IdentityManagerV2 implementations.
• Provide a single call that handles both verification and execution, reducing complexity for consuming contracts.
• Enhance security guarantees by including nullifier and expiration parameters to prevent replay and stale proofs.

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Next Steps

• Implement verifyAndExecute in the main IdentityManagerV2 contract.
• Add unit and integration tests to validate:
  • Proof validity checks.
  • Expiration handling.
  • Replay protection with nullifierHash.
• Document expected consumer usage patterns.