✨ feat: implement API key authentication and user session management

web/lib/browser-notifications.ts

@@ -0,0 +1,50 @@
+export interface BrowserNotificationOptions {
+  title: string;
+  body?: string;
+  onClick?: () => void;
+}
+
+class BrowserNotificationService {
+  async requestPermission(): Promise<boolean> {
+    if (typeof window === "undefined") return false;
+    if (!("Notification" in window)) return false;
+    if (Notification.permission === "granted") return true;
+    if (Notification.permission === "denied") return false;
+
+    const result = await Notification.requestPermission();
+    return result === "granted";
+  }
+
+  async send(options: BrowserNotificationOptions): Promise<void> {
+    if (typeof window === "undefined") return;
+    if (!("Notification" in window)) return;
+    // Only notify when the tab is in the background
+    if (!document.hidden) return;
+
+    const granted = await this.requestPermission();
+    if (!granted) return;
+
+    const n = new Notification(options.title, {
+      body: options.body,
+      icon: "/favicon.ico",
+    });
+
+    n.onclick = () => {
+      window.focus();
+      options.onClick?.();
+      n.close();
+    };
+  }
+
+  getPermission(): NotificationPermission {
+    if (typeof window === "undefined") return "default";
+    if (!("Notification" in window)) return "denied";
+    return Notification.permission;
+  }
+
+  isSupported(): boolean {
+    return typeof window !== "undefined" && "Notification" in window;
+  }
+}
+
+export const browserNotifications = new BrowserNotificationService();