docs(README): add push notifications feature description

- Add detailed information about the push notification system
- Include features like multi-provider architecture, remote provider switching, intelligent deep-linking, and foreground notification handling
- Highlight the advantages for users and content providers

Author: fulleni

README.md

@@ -43,6 +43,16 @@ Give users the tools to find exactly what they're looking for with a multi-facet
 - **Dedicated Discovery Hub:** Users can browse publishers by category in horizontally scrolling carousels, apply regional filters, and perform targeted searches.
 > **Your Advantage:** Deliver powerful content discovery tools that keep users engaged, increase session duration, and encourage return visits.
 
+---
+
+### 🔔 Proactive & Flexible Push Notifications
+A robust, backend-driven notification system keeps users informed and brings them back to the content they care about.
+- **Multi-Provider Architecture:** Built on an abstraction that supports any push notification service. It ships with production-ready providers for Firebase (FCM) and OneSignal.
+- **Remote Provider Switching:** The primary notification provider is selected via remote configuration, allowing you to switch services on the fly without shipping an app update.
+- **Intelligent Deep-Linking:** Tapping a notification opens the app and navigates directly to the relevant content, such as a specific news article, providing a seamless user experience.
+- **Foreground Notification Handling:** Displays a subtle in-app indicator when a notification arrives while the user is active, avoiding intrusive alerts.
+> **Your Advantage:** You get a highly flexible and scalable notification system that avoids vendor lock-in and is ready to re-engage users from day one.
+
 </details>
 
 <details>