feat: add Night Shift layer (boot intro, ops strip, headlight, chapter numerals, film grain)

src/lib/operations.ts

@@ -0,0 +1,38 @@
+export interface Uptime {
+  readonly months: number;
+  readonly days: number;
+}
+
+/** Whole calendar months plus remaining days since `start`, clamped to zero. */
+export function uptimeSince(start: Date, now: Date): Uptime {
+  if (now.getTime() <= start.getTime()) return { months: 0, days: 0 };
+  let months = (now.getUTCFullYear() - start.getUTCFullYear()) * 12 + (now.getUTCMonth() - start.getUTCMonth());
+  let anchor = addMonths(start, months);
+  if (anchor.getTime() > now.getTime()) {
+    months -= 1;
+    anchor = addMonths(start, months);
+  }
+  const days = Math.floor((now.getTime() - anchor.getTime()) / 86_400_000);
+  return { months, days };
+}
+
+function addMonths(date: Date, months: number): Date {
+  return new Date(Date.UTC(
+    date.getUTCFullYear(),
+    date.getUTCMonth() + months,
+    date.getUTCDate(),
+    date.getUTCHours(),
+    date.getUTCMinutes(),
+  ));
+}
+
+const clockFormat = new Intl.DateTimeFormat('en-GB', {
+  hour: '2-digit',
+  minute: '2-digit',
+  hourCycle: 'h23',
+  timeZone: 'Europe/Bucharest',
+});
+
+export function bucharestClock(now: Date): string {
+  return clockFormat.format(now);
+}