novuhq/novu ? reverse-engineered prompt

I need to build a notification system for my app. The core idea is to have a single API that can handle sending messages across multiple channels like email, SMS, push, and an in-app feed. I want a backend service and a simple admin dashboard where my team can manage notification templates and create workflows for when to send what. For example, "send an email and an in-app notification when a user gets a new follower."

The most important part for the user-facing side is an embeddable notification inbox, like a bell icon with a dropdown, that I can easily put into my React application. This should update in real-time. I'll also need a component for users to manage their own notification preferences. The system should integrate with popular providers like SendGrid or Twilio. Please build this using TypeScript, with a Node.js backend.