fix(auth): don't log out fullscreen routes (POS/queue) on refresh

The (fullscreen) layout redirected to /login whenever user.accessToken was
falsy — but on a page refresh that fires before Zustand finishes rehydrating
the persisted auth from localStorage, so an authenticated user was bounced to
login on every refresh. Gate the redirect on _hasHydrated (and show a loader
while rehydrating), matching RouteGuard. Tokens themselves are already long
(30d access / 365d refresh), so sessions now survive refreshes as expected.

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

web/dashboard/src/app/[locale]/(fullscreen)/layout.tsx

@@ -2,24 +2,39 @@
 
 import { useEffect } from "react";
 import { useLocale } from "next-intl";
+import { Loader2 } from "lucide-react";
 import { useRouter } from "@/i18n/routing";
 import { useAuthStore } from "@/lib/stores/auth.store";
 import { RouteGuard } from "@/components/auth/route-guard";
 
-/** Full-viewport routes (queue TV display) — auth only, no dashboard chrome. */
+/** Full-viewport routes (POS, queue TV display) — auth only, no dashboard chrome. */
 export default function FullscreenLayout({ children }: { children: React.ReactNode }) {
   const locale = useLocale();
   const router = useRouter();
   const user = useAuthStore((s) => s.user);
+  const hasHydrated = useAuthStore((s) => s._hasHydrated);
+  const dir = locale === "en" ? "ltr" : "rtl";
 
   useEffect(() => {
-    if (!user?.accessToken) {
+    // Only redirect AFTER the persisted auth has rehydrated from localStorage —
+    // otherwise a page refresh sees the empty initial state and bounces an
+    // already-authenticated user to /login before their session loads back in.
+    if (hasHydrated && !user?.accessToken) {
       router.replace("/login");
     }
-  }, [user, router]);
+  }, [hasHydrated, user, router]);
+
+  // While rehydrating, show a loader instead of redirecting or flashing content.
+  if (!hasHydrated) {
+    return (
+      <div className="flex min-h-svh items-center justify-center" dir={dir}>
+        <Loader2 className="size-6 animate-spin text-muted-foreground" />
+      </div>
+    );
+  }
 
   return (
-    <div className="min-h-svh" dir={locale === "en" ? "ltr" : "rtl"}>
+    <div className="min-h-svh" dir={dir}>
       <RouteGuard>{children}</RouteGuard>
     </div>
   );