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]

I would suggest making one of these two changes:

1. Either do not enforce executor to be the owner of executor_token
2. Or do not enforce executor to be equal to prepared_order_response.prepared_by. Instead, add another field that will be linked to this account and to which the SOL from closed account will be returned.

Our requirement is simple, we just need SOL to be returned to a wallet that pays for tx fees and rent (across all transactions) and USDC returned to a token account which is not owned by this wallet.

[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? c6bd633