export const appendCapped = <T>(
  prev: T[],
  next: T[],
  max: number,
  onDrop?: (item: T) => void
) => {
  const merged = [...prev, ...next]
  if (merged.length <= max) return merged
  const dropCount = merged.length - max
  if (onDrop) {
    for (let i = 0; i < dropCount; i += 1) onDrop(merged[i])
  }
  return merged.slice(dropCount)
}