Handle smart contract wallets in validateClusterLock()

[OisinKyne]

🎯 Problem to be solved

Identified while talking to the Byzantine team. The client.validateClusterLock() method fails for EIP1271 smart contract signatures in the operator field of a cluster lock.

🛠️ Proposed solution

Potentially if a signature fails a normal check we can try a 1271 check? It would be quite heavy on reads of the chain if there are a lot of them, so we wouldn't want to do it by default ideally.

🧪 Tests

• Netlify deployment build tests passing

👐 Additional acceptance criteria

❌ Out of Scope

Can create a separate issue to use this change in Obol API