export interface ThreadFeedScrollMetrics {  readonly contentHeight: number;  readonly viewportHeight: number;  readonly offsetY: number;  readonly bottomInset: number;} export function threadFeedDistanceFromEnd(metrics: ThreadFeedScrollMetrics): number {  return metrics.contentHeight + metrics.bottomInset - metrics.viewportHeight - metrics.offsetY;} export function isThreadFeedNearEnd(metrics: ThreadFeedScrollMetrics, threshold: number): boolean {  return threadFeedDistanceFromEnd(metrics) <= threshold;} export function resolveThreadFeedBottomInset(input: {  readonly estimatedOverlayHeight: number;  readonly measuredOverlayHeight: number;  readonly gap: number;}): number {  return Math.max(input.estimatedOverlayHeight, input.measuredOverlayHeight) + input.gap;}