Add in-app + real-time notifications (SignalR/mock, Iran-friendly)

- AppNotification + OnlineService.onNotification (hub event + mock periodic) —
  no FCM/APNs (blocked in Iran); uses the existing realtime channel
- notification-store + pushNotification(); 🔔 bell with unread badge in TopBar,
  notifications screen, global toaster (plays notify sfx)
- Wired events: daily reward, post-match achievements, friend requests
- Closed-app push (Pushe/Najva/Chabok) noted as a later step (needs provider keys)

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

src/components/online/TopBar.tsx

@@ -1,8 +1,9 @@
 "use client";
 
-import { Coins, Crown, Gift } from "lucide-react";
+import { Bell, Coins, Crown, Gift } from "lucide-react";
 import { useSessionStore } from "@/lib/session-store";
 import { useUIStore } from "@/lib/ui-store";
+import { useNotifStore } from "@/lib/notification-store";
 import { useI18n } from "@/lib/i18n";
 import { Avatar } from "./Avatar";
 
@@ -10,6 +11,7 @@ export function TopBar() {
   const profile = useSessionStore((s) => s.profile);
   const go = useUIStore((s) => s.go);
   const openDaily = useUIStore((s) => s.openDaily);
+  const unread = useNotifStore((s) => s.unread);
   const { t } = useI18n();
   if (!profile) return null;
 
@@ -34,6 +36,18 @@ export function TopBar() {
       </button>
 
       <div className="flex items-center gap-2">
+        <button
+          onClick={() => go("notifications")}
+          className="glass rounded-full p-2 hover:bg-navy-800/80 transition relative"
+          title={t("notif.title")}
+        >
+          <Bell className="size-4 text-gold-400" />
+          {unread > 0 && (
+            <span className="absolute -top-0.5 ltr:-right-0.5 rtl:-left-0.5 min-w-4 h-4 px-1 rounded-full bg-rose-500 text-[9px] font-bold text-white flex items-center justify-center">
+              {unread > 9 ? "9+" : unread}
+            </span>
+          )}
+        </button>
         <button
           onClick={openDaily}
           className="glass rounded-full p-2 hover:bg-navy-800/80 transition"