feat(contract): implement bounded resumable settlement and void refunds

[karagozemin]

Difficulty

Hard — production engineering across multiple components; a small cleanup or test-only patch does not complete this issue.

Context

The contract permits up to 500 bidders while settle iterates over all bidders and performs transfers in one call. Extend existing conservation tests into a bounded settlement protocol whose progress survives separate transactions.

Starting points

• contracts/round/src/lib.rs
• contracts/round/src/storage.rs
• contracts/round/src/types.rs
• packages/sdk/src/client.ts

Scope

• Design explicit payout progress with bounded batch size for settlement and void refunds.
• Freeze the clearing result before payouts and preserve current winner, tie-breaking and refund amounts.
• Prevent already-paid entries from being paid again under repeated or overlapping permissionless calls.
• Update generated bindings, SDK/keeper orchestration and user-visible progress.

Acceptance criteria

• A maximum-bidder round completes through bounded calls with recorded CPU/memory/read/write budgets.
• After every successful batch, original escrow equals paid amounts plus remaining obligations.
• Repeated and overlapping batches cannot duplicate operator payment, winner surplus or loser refunds.
• An interrupted or failed batch can resume from confirmed state without skipping obligations.
• Settled/fully-refunded status is emitted only after all obligations are completed.
• Tests cover cleared and voided rounds, zero surplus, final short batch and invalid cursors.

Verification

Run contract property/model tests and a 500-bidder resource regression fixture. Interrupt the keeper between every batch and compare final balances with the original settlement model. Document deployment/ABI compatibility without deploying.

Out of scope

Changing bid ranking, fees, token choice, introducing discretionary withdrawals, or executing public-network deployments.

[Iker2522]

I am applying to take ownership of this issue.I will implement bounded, resumable settlement and void refunds in Sub-Rosa-Issue / sub-rosa-issue.I will refactor the settlement logic in contracts/round/src/lib.rs to break unbounded bidder loops into stateful, bounded batch iterations. Clearing state (winning clearing price, tie-breakers, and refund allocations) will freeze on initial settlement call, while persistent payout cursors in storage.rs will track completion state to prevent double-payouts under concurrent or repeated permissionless invocations.I will update packages/sdk/src/client.ts and keeper orchestration to handle multi-batch settlement loops, update generated contract bindings, and ensure Settled/Voided status events fire only when all obligations are zeroed.I will verify the delivery using 500-bidder resource budget benchmarks, property conservation tests ($E_{\text{original}} = \text{Paid} + \text{Remaining}$), mid-batch keeper interruption recovery tests, and invalid cursor rejection tests. PR ready in 48 hours. Closes #359.

[ZacLou]

I am a senior full-stack developer with 15+ years of experience. I have deep expertise in smart contract development, settlement systems, and building secure financial applications. I have implemented bounded resumable settlement, void refunds, and complex payment flows in production. Ready to start immediately.

[Joyful12-tech]

Hello Maintainer! I'd like to work on this issue. I can deliver it following the requirements and submit a quality PR within 2 days. Thank you!

[ranjeet150]

Hey team,

I can tackle feat(contract): implement bounded resumable settlement and void refunds. Proposed implementation roadmap:

• Analysis: Inspect current behavior and edge cases in Sub-Rosa-Issue/sub-rosa-issue
• Implementation: Implement feat(contract): implement bounded resumable settlement and void refunds with explicit require_auth checks, clean storage layouts, and robust Soroban contract logic.
• Testing: Add comprehensive unit tests verifying both happy-path invocations and unauthorized revert scenarios.
• PR: Atomic commit with clean git hygiene and passing CI

Happy to pick this up today—please assign to me!

[guptakumarranjeet150]

Hello! I'd like to work on this issue.

I would love to take this on. My planned approach:

• Implement feat(contract): implement bounded resumable settlement and void refunds with explicit require_auth checks, clean storage layouts, and robust Soroban contract logic.
• Add comprehensive unit tests verifying both happy-path invocations and unauthorized revert scenarios.

Looking forward to contributing—please feel free to assign!