VALIDATION REQUEST: GP5 V2 Snapshot Fix vs Nethermind Approach

We need to fix GP5 node stuck at block 56,830,293 (Apothem V2 checkpoint).

PROPOSED FIX (3 changes):

1. Replace hard error at engine.go:758-760 with repairSnapshot call
2. Generalize repairSnapshot's firstV2Checkpoint state-read to ALL checkpoints
3. Remove Version gate, keep only candidate count == 13 check

NETHERMIND COMPARISON NEEDED:
- Nethermind uses snap sync + separate consensus state
- Doesn't have V1/V2 transition complexity
- Validator sets stored independently

QUESTIONS:
1. Is the proposed fix architecturally sound compared to Nethermind?
2. Should we instead implement a Nethermind-like approach (separate consensus DB)?
3. What are the risks of the proposed fix?
4. Is there a simpler fix that aligns better with v2.6.8 behavior?

Please validate and advise.