Function trendByWeek

src/cli/maintain-stats.ts:84–95

(runs: MaintainRun[], nowMs: number, weeks = 8)

/** Opened-cleanups per week over the last `weeks` (oldest→newest) — a sparkline series. PURE. */
export function trendByWeek(runs: MaintainRun[], nowMs: number, weeks = 8): number[] {
  const DAY = 86_400_000;
  const buckets = new Array(weeks).fill(0);
  for (const r of runs) {
    if (r.status !== 'opened' || !r.at) continue;
    const t = Date.parse(r.at);
    if (!Number.isFinite(t)) continue;
    const weeksAgo = Math.floor((nowMs - t) / (7 * DAY));
    if (weeksAgo >= 0 && weeksAgo < weeks) buckets[weeks - 1 - weeksAgo]++;   // newest at the end
  }
  return buckets;
}

/** Project the going rate forward: cleanups + minutes saved per month, from the last 28 days. PURE. */
export function projectMonthly(runs: MaintainRun[], nowMs: number): { cleanupsPerMonth: number; minutesPerMonth: number } {