implement a threshold-based recombination

[boulder225]

🎯 Problem to be solved

The current key recombining process requires all key shares to be present, contradicting the resilience feature of DVT as suggested in the docs. The CLI reference mentions all key shares need to be present.

09:11:50.294 ERRO cmd Fatal error: not all private key shares found for validator {"validator_index": 0, "expected": 4, "actual": 3}

🛠️ Proposed solution

• Research how to implement a threshold-based recombination instead of requiring all key shares.
• Conduct a risk assessment to weigh the trade-offs between resilience and the potential for collusion.
• Update documentation to reflect any changes made.

[dB2510]

Closed by #2664