Session revocation mechanism

Opus provides on-chain session revocation:

mapping(address => bool) public isRevoked;

function revokeSession(address sessionKey) external onlyOwner {
    isRevoked[sessionKey] = true;
}

function isSessionActive(address key) public view returns (bool) {
    return !isRevoked[key] && sessions[key].validUntil > block.timestamp;
}

Frontend includes a revocation panel:

/+-------------------------+
|  Active Sessions        |
+-------------------------+
| • 0x1234...abcd         |
|   [Revoke]              |
+-------------------------+