feat: Extend MultiSigContractV2 with Constructor, Constants, and Governance Controls

[SynnekOG]

Summary

This PR significantly extends the functionality of MultiSigContractV2 by adding custom errors, governance-related constants, a reference to external contracts, and a constructor for initializing critical parameters. These changes lay the foundation for secure multisignature governance, attestation integration, and emergency management.

---

Changes

🔒 New Custom Errors

• MultiSigContract__TimelockActive
  Raised when a transaction cannot execute due to an active timelock.
• MultiSigContract__EmergencyModeActive
  Prevents execution of certain functions during emergency mode.
• MultiSigContract__InvalidThreshold
  Thrown when an invalid global signature threshold is set.
• MultiSigContract__DuplicateSigner
  Prevents duplicate signer entries.

---

⚙️ New State Variables

• Factory Token Reference

  • FactoryTokenContract public factoryTokenContract;
    Reference to the factory’s token contract for tighter integration.

• Sign Protocol Instance

  • ISP public spInstance;
    Enables integration with Sign Protocol for attestations.

• Schema IDs

  • uint64 public signatureSchemaId;
  • uint64 public revocationSchemaId;
  • uint64 public executionSchemaId;
    Each schema ID represents a different type of attestation (signatures, revocations, executions).

• Signature Threshold

  • uint256 public signatureThreshold = 6000;
    Default 60% global signature threshold, represented as percentage * 100.

• Emergency Controls

  • bool public emergencyMode; – Tracks whether the contract is in emergency mode.
  • address public emergencyAdmin; – Privileged account capable of pausing/unpausing during emergencies.

---

🏗 Constructor

constructor(
    address _spInstance,
    uint64 _signatureSchemaId,
    uint64 _revocationSchemaId,
    uint64 _executionSchemaId,
    address _emergencyAdmin,
    address _initialOwner
) Ownable(_initialOwner) {
    if (_spInstance == address(0) || _emergencyAdmin == address(0)) {
        revert MultiSigContract__InvalidAddress();
    }

    spInstance = ISP(_spInstance);
    signatureSchemaId = _signatureSchemaId;
    revocationSchemaId = _revocationSchemaId;
    executionSchemaId = _executionSchemaId;
    emergencyAdmin = _emergencyAdmin;

    // Potential future addition: add initial owner as default signer with admin role
}