Stake.nextPositionId starts at 654_321, so attack files cannot use literal
on-chain IDs (e.g. positionId=1 always reverts with PositionNotFound).
Fix AttackRunner to treat the JSONL positionId field as a 1-based index into
the list of positions created by stake ops during the current run:
- Add IStake.snatch returns (uint256) to the interface so the returned ID is
captured.
- Track returned IDs in _stakedPositionIds[] (inserted in creation order).
- _executeUnstake resolves positionId to _stakedPositionIds[positionId-1]
before calling exitPosition, matching the natural "unstake position 1"
semantics in the attack DSL.
KRK approval for Stake was already present in _setup(); no other changes needed.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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