Fee logic ignores cancellation

[adamazad]

When orders are created, the OrderFactory substracts the fee from the principal:

https://github.com/ImpeccableHQ/stackly/blob/7bfd49daa0730577fb5f5f43d6c879cc533c719c/packages/contracts/src/OrderFactory.sol#L58-L59

This is problematic when canceling orders: the fee is not returned to the user. For instance, if a user deposits $1000, $1 is immediately paid to the protocol.

https://github.com/ImpeccableHQ/stackly/blob/7bfd49daa0730577fb5f5f43d6c879cc533c719c/packages/contracts/src/DCAOrder.sol#L125-L133

Protocol fees should be paid upon successful execution of orders.

[NelsonGaldeman]

Good point, but it would make fee structure much more complex (and expensive gas-wise, also irrelevant on L2s).

I will think of possible easier to implement design solutions, but defo not for the first release. Thanks for the suggestion Adam!