fix(appointments): detail page back/breadcrumb return to the appointment day

AppointmentDetailPage now derives the appointment's local day from slot_start
and points both the «بازگشت» button and the «نوبت‌ها» breadcrumb to
/admin/appointments?date=<that day>, so viewing/acting on an appointment from
any day returns to that day instead of today.

Test: the «نوبت‌ها» breadcrumb links back to the appointment's date.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

assets/admin/pages/AppointmentDetailPage.tsx

@@ -22,6 +22,13 @@ const ALL_STATUSES: { value: AppointmentStatus; label: string }[] = [
   { value: 'expired',             label: 'منقضی' },
 ];
 
+// روزِ محلیِ نوبت (YYYY-MM-DD) برای بازگشت به همان تاریخ در لیست.
+const isoDay = (ts?: number | null) => {
+  if (!ts) return '';
+  const d = new Date(ts * 1000);
+  return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;
+};
+
 const timeOf = (ts?: number | null) => {
   const d = toDate(ts ?? null);
   return d
@@ -73,6 +80,9 @@ export default function AppointmentDetailPage() {
 
   // پاسخ single تودرتو است: { data: { data: {...} } }
   const appt: any = (data?.data as any)?.data ?? data?.data;
+  // بازگشت به همان روزِ نوبت (نه امروز).
+  const day = isoDay(appt?.slot_start);
+  const backTo = day ? `/admin/appointments?date=${day}` : '/admin/appointments';
 
   return (
     <div>
@@ -80,11 +90,11 @@ export default function AppointmentDetailPage() {
         title="جزئیات نوبت"
         breadcrumbs={[
           { label: 'داشبورد', to: '/admin/dashboard' },
-          { label: 'نوبت‌ها', to: '/admin/appointments' },
+          { label: 'نوبت‌ها', to: backTo },
           { label: 'جزئیات' },
         ]}
         action={
-          <button onClick={() => navigate('/admin/appointments')}
+          <button onClick={() => navigate(backTo)}
             className="flex items-center gap-2 text-sm text-slate-500 dark:text-slate-400 hover:text-slate-800 dark:hover:text-slate-100 transition-colors">
             <ArrowRightIcon className="w-4 h-4" />
             بازگشت