feat(admin-web): add web/admin to repo

Initial commit of the Super-Admin web panel (Next.js + TypeScript).
CI admin-web-check job was failing because the directory was never
tracked in git.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/admin/src/lib/format-datetime.ts

@@ -0,0 +1,30 @@
+import { format } from "date-fns-jalali";
+import { enUS } from "date-fns-jalali/locale/en-US";
+import { faIR } from "date-fns-jalali/locale/fa-IR";
+
+const PLAN_TIERS = ["Free", "Pro", "Business", "Enterprise"] as const;
+export type PlanTierKey = (typeof PLAN_TIERS)[number];
+
+export function isPlanTierKey(tier: string): tier is PlanTierKey {
+  return (PLAN_TIERS as readonly string[]).includes(tier);
+}
+
+export function numberLocaleForUi(locale: string): string {
+  if (locale === "en") return "en-US";
+  if (locale === "ar") return "ar-SA";
+  return "fa-IR";
+}
+
+export function formatHeaderTime(date: Date, locale: string): string {
+  return date.toLocaleTimeString(numberLocaleForUi(locale), {
+    hour: "2-digit",
+    minute: "2-digit",
+    second: "2-digit",
+    hour12: false,
+  });
+}
+
+export function formatHeaderJalaliDate(date: Date, locale: string): string {
+  const jalaliLocale = locale === "en" ? enUS : faIR;
+  return format(date, "EEEE d MMMM yyyy", { locale: jalaliLocale });
+}