[bug] validator: late dest-tip snapshot rejects honest fulfillment after RPC retry

[dearsishs]

[bug] validator: late dest-tip snapshot rejects honest fulfillment after RPC retry

Component: allways/validator/chain_verification.py

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Summary

observe_initiation() records the dest-chain tip on first successful RPC. If the first snapshot fails and the miner fulfills before a retry succeeds, the snapshot can be taken after the payout block. is_dest_tx_fresh() then rejects the honest tx as a replay, blocking confirm_swap and risking timeout/slash.

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Suggested fix

When swap.to_tx_block > 0, cap the stored tip with min(tip, swap.to_tx_block).