fix: wait for hydration before checking auth in NotificationHandler

app/components/NotificationHandler.js

@@ -1,33 +1,44 @@
 "use client";
 
-import { useEffect, useState } from "react";
+import { useEffect, useState, useRef } from "react";
 import { requestNotificationPermission, onForegroundMessage } from "../utils/firebase";
 import AuthService from "../services/AuthService";
 
 export default function NotificationHandler() {
   const [notification, setNotification] = useState(null);
-  const [unsubscribe, setUnsubscribe] = useState(null);
+  const initialized = useRef(false);
 
   useEffect(() => {
-    const user = AuthService.getUser();
-    if (!user) return;
+    // Wait for hydration to complete
+    const timer = setTimeout(() => {
+      if (initialized.current) return;
+      initialized.current = true;
 
-    // User is signed in — request permission and listen for messages
-    requestNotificationPermission().then((token) => {
-      if (token) {
-        console.log("[Notifications] FCM token obtained");
+      const token = AuthService.getToken();
+      if (!token) {
+        console.log("[Notifications] Not signed in, skipping");
+        return;
       }
-    });
 
-    const unsub = onForegroundMessage((payload) => {
-      const title = payload.notification?.title || payload.data?.title || "Sweet Home";
-      const body = payload.notification?.body || payload.data?.body || "";
-      setNotification({ title, body });
-      setTimeout(() => setNotification(null), 5000);
-    });
+      console.log("[Notifications] Signed in, requesting permission...");
+      requestNotificationPermission().then((fcmToken) => {
+        if (fcmToken) {
+          console.log("[Notifications] FCM token obtained:", fcmToken.substring(0, 20) + "...");
+        }
+      });
 
-    setUnsubscribe(() => unsub);
-    return () => unsub();
+      const unsub = onForegroundMessage((payload) => {
+        const title = payload.notification?.title || payload.data?.title || "Sweet Home";
+        const body = payload.notification?.body || payload.data?.body || "";
+        setNotification({ title, body });
+        setTimeout(() => setNotification(null), 5000);
+      });
+
+      // Cleanup on unmount
+      return () => unsub();
+    }, 1000); // Wait 1s for hydration
+
+    return () => clearTimeout(timer);
   }, []);
 
   if (!notification) return null;