React Chat Room Component with Live Features

Context

You are building a React chat room component using the PubNub Chat SDK. The component receives a channel object (already created via the Chat SDK) and the chat instance as props. The chat room should feel responsive and interactive, showing who else is actively composing messages.

Task

Write a React functional component (ChatRoom.jsx) that:

1. Displays incoming messages in real time as they arrive
2. Provides a text input and send button for composing messages
3. Shows an indicator when other users are composing messages
4. Properly manages all subscriptions and resources when the component unmounts
5. Handles the composing indicator efficiently to avoid excessive signaling

Expected Outputs

• A ChatRoom.jsx file containing a complete React functional component with real-time messaging and active composition display.