The grant_position function is to require that a position must not have an owner before granting ownership as hinted here. Albeit, the function does not enforce this requirement. The function directly sets the new owner without verifying if the position is already owned, which could allow unauthorized overwriting of position ownership.
https://github.com/code-423n4/2024-10-superposition/blob/7ad51104a8514d46e5c3d756264564426f2927fe/pkg/seawater/src/lib.rs#L453-L462
This could allow unauthorized transfers of position ownership, going against the intention.
Consider adding a check at the beginning of the grant_position function to verify that the positions current owner is Address::ZERO before proceeding with the ownership transfer. Also add a new error msg to handle cases where a position is already owned.
