Function verify_slot_drafts 

pub fn verify_slot_drafts(slot_idx: usize, num_drafts: usize) -> usize

Env-reading wrapper of verify_slot_drafts_with: the ladder policy (with its ATLAS_MTP_K_LADDER / ATLAS_NO_MTP_K_LADDER overrides — a disabled ladder returns num_drafts at every width, making the tiers vacuous) plus the mtp_pool_full_width kill switch.