Improve README with comprehensive overview, tech stack, architecture and usage instructions

[Copilot]

Enhanced the README.md file to provide a complete overview of the NextJS Vertical Microfrontends project, transforming it from a minimal placeholder into comprehensive documentation.

What's Added

Project Overview

• Clear explanation of vertical microfrontends concept and how it differs from horizontal microfrontends
• Business value proposition and use cases
• Real-world examples of vertical slices (auth, products, cart, orders)

Technical Documentation

• Complete tech stack overview featuring NextJS Multi-Zones, React, TypeScript, and Node.js
• Detailed architecture diagrams showing multi-zone structure and communication patterns
• Project structure layout for future implementation

Developer Experience

• Step-by-step local development setup instructions
• Prerequisites and dependency management
• Development workflow guidance
• Production build and deployment strategies

Additional Sections

• Benefits and challenges of the vertical microfrontends approach
• Contributing guidelines for open source collaboration
• Roadmap outlining planned implementation phases
• Useful resources and documentation links

The README now serves as a comprehensive guide for developers interested in understanding and implementing vertical microfrontends using NextJS Multi-Zones, providing both conceptual understanding and practical implementation guidance.

Fixes #1.

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[Copilot]

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