fix: print the date the countdown is actually counting to

The detail sheet formatted the stored ISO, so a day-precision end rendered
as 00:00Z — the previous day for every reader west of UTC, and now a
different day from the timer sitting beside it. Both dates come off the
clock instead, which resolves them the same way.

The note under them said the end was "accurate to the day only" and left
it there. It can say where the count actually lands, and should: a reader
deciding whether to log in tonight wants the reset, not a shrug. It still
says this is a reading rather than a time the source printed.

REGION_LABEL moves next to the region table it names, which is also how
the note gets "Europe" rather than the raw id.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

src/shared/time.ts

@@ -21,6 +21,13 @@ export const REGION_RESET_UTC_OFFSET: Record<Region, number> = {
   europe: 1,
 };
 
+/** What a region is called when the reader is shown one. */
+export const REGION_LABEL: Record<Region, string> = {
+  america: "America",
+  europe: "Europe",
+  asia: "Asia",
+};
+
 /**
  * Gacha servers roll the day at 04:00 local server time, not midnight — a
  * player finishing at 02:00 is still on the previous day's dailies. Getting
@@ -224,8 +231,16 @@ export function formatRemaining(msRemaining: number): string {
   return `${seconds}s`;
 }
 
-/** Absolute date for the detail view, in the reader's own timezone. */
-export function formatAbsolute(iso: string, withTime: boolean): string {
+/**
+ * Absolute date for the detail view, in the reader's own timezone.
+ *
+ * Takes an instant rather than only an ISO string so a caller with a resolved
+ * boundary can print the one the countdown is counting to. A day-precision date
+ * read straight off the event says 00:00Z, which renders as the *previous* day
+ * to every reader west of UTC — the sheet would then name one day while the
+ * timer beside it ran to another.
+ */
+export function formatAbsolute(iso: string | number, withTime: boolean): string {
   const d = new Date(iso);
   const date = d.toLocaleDateString(undefined, {
     weekday: "short",