Constant PACING_RECIPIENT_CAP 

pub const PACING_RECIPIENT_CAP: usize = 1024;

Idle-state LRU cap on the pacing wrapper’s per-recipient rows. Bounds growth when a bot legitimately serves many thousands of distinct peers. Eviction only reclaims idle rows (no queued sends, no running worker, no in-flight dispatch), so under a pathological all-active burst the row count can temporarily exceed this target until rows become idle — it is not an unconditional hard bound. Each recipient’s queue depth stays bounded regardless. Not exposed in config — promote to a schema field if an operator reports hitting it.