Flutter To-Do App & Node.js

I need a straightforward cross-platform to-do application built with Flutter for both Android and iOS, backed by a lightweight Node.js REST API. The core feature is simple but polished task management that lets a user create, edit, and delete tasks, each with an optional due date clearly shown in the list and on the task-detail screen.

For the backend, please spin up a clean Node.js (Express) project that exposes endpoints for those task operations and stores everything in MongoDB. All data exchanges should be in JSON.

Access to the app will be protected by email-and-password authentication. A short registration flow, secure login, JWT-based session handling, and guarded routes on the API side are part of the scope. No social sign-ins are required.

Deliverables
• Flutter source code compiling on the latest stable channel for Android and iOS
• Node.js + Express code with clear folder structure and environment variable support
• MongoDB schema and any necessary seed scripts
• Postman (or similar) collection demonstrating each endpoint
• Brief README covering setup, environment variables, build/run commands, and any third-party packages used

Acceptance criteria
The app must install on both platforms, let a new user sign up, log in, create a task, assign a due date, see it persist after app restart, and delete it successfully. API responses should return the correct HTTP status codes and standard error handling.