solana: pay the original payers back

[a5-pickle]

• Add prepared_by to Auction account to save original rent payer when placing the initial offer
• Enforce beneficiary to always be prepared_by on PreparedOrderResponse when settling a complete auction
  • If there is no penalty when executing the order, which this settlement is based on, the total repayment (including base fee) will go to the best offer token still
  • If there is a penalty, we want to pay the "liquidator" (beneficiary), who will have specified which token account to send the base fee to
• Fix tests

[livthomas]

We have found another issue in add_auction_history_entry. There are two parameters:

• beneficiary
  • receives SOL from closed auction account
• beneficiary_token
  • needs to be owned by beneficiary
  • needs to be equal to initial_offer_token

I think after changes made in this PR, beneficiary_token is no longer needed. You can add a constraint directly on beneficiary so it would need to be equal to auction. prepared_by.

[a5-pickle]

We have found another issue in add_auction_history_entry. There are two parameters:

• beneficiary

  • receives SOL from closed auction account

• beneficiary_token

  • needs to be owned by beneficiary
  • needs to be equal to initial_offer_token

I think after changes made in this PR, beneficiary_token is no longer needed. You can add a constraint directly on beneficiary so it would need to be equal to auction. prepared_by.

Very good catch! How does this look? https://github.com/wormhole-foundation/example-liquidity-layer/pull/193/commits/c6bd633745634f4be688aacf67c307c6a027b8c4