Collaborative Todo List

Problem Description

A team productivity app needs a shared todo list where multiple users can add, complete, and delete tasks in real time. When one user makes a change, all other users viewing the same list see the update instantly.

Build a Node.js/Express backend and React/TypeScript frontend:

• Users can create, toggle (complete/incomplete), and delete todo items
• Changes made by one user appear instantly for all other users viewing the same list
• Each todo list has a unique ID so users can share a link to collaborate
• Todos have: id, listId, text, completed, createdBy, createdAt
• Multiple todo lists can exist simultaneously

Output Specification

Produce the following in a src/ directory:

Server:

• src/server.ts -- Express server with real-time collaboration
• src/todos.ts -- Todo CRUD operations and storage

Client:

• src/components/TodoList.tsx -- The collaborative todo list view
• src/components/TodoItem.tsx -- Single todo item component
• src/hooks/useTodoList.ts -- Hook that manages the real-time connection for a specific todo list

Use in-memory storage. Do not include test files or build configuration.