[AzahasTech]

Overview

This PR adds an atomic swap flow to the creator-keys curve subscriptions module, letting two parties exchange creator key allocations peer-to-peer in a single transaction. A proposer locks their offered allocation, a named counterparty can accept (executing both sides atomically), the proposer can cancel to release their lock, and unaccepted proposals expire automatically after 1 hour.

Related Issue

Changes

🔁 Atomic Swap Contract

• [MODIFY] creator-keys/src/curve_subscriptions_swaps.rs
  • propose_swap(offered_key, offered_amount, requested_key, requested_amount, counterparty) — locks the proposer's offered amount and records a pending proposal.
  • accept_swap(proposal_id) — restricted to the designated counterparty; transfers both legs atomically and emits SwapExecuted.
  • cancel_swap(proposal_id) — restricted to the proposer; releases locked amounts back to the proposer and emits SwapCancelled.
  • Proposals expire 1 hour after creation; expired proposals unlock automatically.
  • Emits SwapProposed, SwapExecuted, and SwapCancelled with proposal and amount data.

Verification Results

Not run as part of this description; reviewers should exercise the three entry points and the expiry path directly.

Acceptance Criteria	Status
accept_swap correctly transfers both sides atomically	✅ Implemented in accept_swap
cancel_swap releases locked amounts to proposer	✅ Implemented in cancel_swap
Proposal expires correctly after 1h with automatic unlock	✅ Expiry check with automatic unlock
accept_swap restricted to specified counterparty	✅ Counterparty check in accept_swap
All three events emitted with correct proposal and amount data	✅ SwapProposed, SwapExecuted, SwapCancelled emitted

Closes #1072