fix(dashboard): Persian Jalali formatting for resource credit dates

Render the prepaid resource credit "remaining" and "expires" text in
Persian with Jalali calendar when locale is fa: localized digits and
day/hour/minute units for time left, and weekday + Jalali date + time
for the expiry. Parts are assembled explicitly so order is stable
regardless of the runtime's ICU pattern data.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/lib/format-utils.ts

@@ -31,11 +31,67 @@ export function formatRemainingDurationMs(remainingMs: number): string {
   return 'less than 1m';
 }
 
-/** Expiry timestamp in the user's locale and timezone. */
-export function formatExpiresAtLocal(expiresAt: string | Date): string {
+/** Persian (با ارقام فارسی) human-readable time left, e.g. «۲۹ روز و ۱۹ ساعت و ۵۱ دقیقه». */
+function formatRemainingDurationFa(remainingMs: number): string {
+  const ms = Math.max(0, remainingMs);
+  const days = Math.floor(ms / 86400000);
+  const hours = Math.floor((ms % 86400000) / 3600000);
+  const minutes = Math.floor((ms % 3600000) / 60000);
+  const fa = (n: number) => n.toLocaleString('fa-IR', { useGrouping: false });
+  const parts: string[] = [];
+  if (days > 0) parts.push(`${fa(days)} روز`);
+  if (hours > 0) parts.push(`${fa(hours)} ساعت`);
+  if (minutes > 0) parts.push(`${fa(minutes)} دقیقه`);
+  if (parts.length === 0) return 'کمتر از ۱ دقیقه';
+  return parts.join(' و ');
+}
+
+/** Locale-aware time left from an expiry timestamp. */
+export function formatRemainingForLocale(
+  expiresAt: string | Date,
+  locale: string,
+): string {
   const date = typeof expiresAt === 'string' ? new Date(expiresAt) : expiresAt;
   if (Number.isNaN(date.getTime())) return '—';
-  return date.toLocaleString(undefined, {
+  const remainingMs = date.getTime() - Date.now();
+  return locale === 'fa'
+    ? formatRemainingDurationFa(remainingMs)
+    : formatRemainingDurationMs(remainingMs);
+}
+
+/**
+ * Expiry timestamp in the user's locale and timezone. For Persian it renders the
+ * Jalali date with weekday and time, e.g. «یکشنبه، ۲۹ تیر ۱۴۰۵، ساعت ۱۹:۵۸».
+ */
+export function formatExpiresAtLocal(
+  expiresAt: string | Date,
+  locale?: string,
+): string {
+  const date = typeof expiresAt === 'string' ? new Date(expiresAt) : expiresAt;
+  if (Number.isNaN(date.getTime())) return '—';
+  if (locale === 'fa') {
+    // Assemble parts explicitly so the order is «روز هفته، روز ماه سال» regardless
+    // of the runtime's ICU pattern data.
+    const parts = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
+      weekday: 'long',
+      year: 'numeric',
+      month: 'long',
+      day: 'numeric',
+    }).formatToParts(date);
+    const get = (type: Intl.DateTimeFormatPartTypes) =>
+      parts.find((p) => p.type === type)?.value ?? '';
+    const weekday = get('weekday');
+    const dayNum = get('day');
+    const month = get('month');
+    const year = get('year');
+    const time = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
+      hour: '2-digit',
+      minute: '2-digit',
+      hour12: false,
+    }).format(date);
+    return `${weekday}، ${dayNum} ${month} ${year}، ساعت ${time}`;
+  }
+  return date.toLocaleString(locale || undefined, {
     dateStyle: 'medium',
     timeStyle: 'short',
   });