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/lib/online-store.ts

@@ -2,6 +2,7 @@
 
 import { create } from "zustand";
 import { CreateRoomOptions, MatchmakingOptions, getService } from "./online/service";
+import { pushNotification } from "./notification-store";
 import {
   ChatMessage,
   Friend,
@@ -49,6 +50,7 @@ let roomUnsub: (() => void) | null = null;
 let mmUnsub: (() => void) | null = null;
 let friendUnsub: (() => void) | null = null;
 let chatUnsub: (() => void) | null = null;
+const seenRequests = new Set<string>();
 
 export const useOnlineStore = create<OnlineStore>((set, get) => ({
   friends: [],
@@ -61,6 +63,18 @@ export const useOnlineStore = create<OnlineStore>((set, get) => ({
     const svc = getService();
     const [friends, requests] = await Promise.all([svc.listFriends(), svc.listRequests()]);
     set({ friends, requests });
+    for (const r of requests) {
+      if (seenRequests.has(r.id)) continue;
+      seenRequests.add(r.id);
+      pushNotification({
+        kind: "friend_request",
+        titleFa: "درخواست دوستی جدید",
+        titleEn: "New friend request",
+        bodyFa: r.from.displayName,
+        bodyEn: r.from.displayName,
+        icon: "👥",
+      });
+    }
     if (!friendUnsub) friendUnsub = svc.onFriends((f) => set({ friends: f }));
   },