feat: Implement py-peer of Universal Connectivity dApp

[sumanjeet0012]

Python Implementation of Universal Connectivity Chat Application

Overview

This PR implements a complete Python peer-to-peer chat application using libp2p and GossipSub protocol, addressing the request for a Python peer in the Universal Connectivity project.

Related Issue

Fixes: libp2p/py-libp2p#624

Implementation Details

Core Features

• Peer-to-Peer Chat: Real-time messaging using GossipSub pubsub protocol
• Multiple UI Modes:
  • Textual TUI interface for rich terminal experience
  • CLI mode for simple interactive chat
  • Headless mode for background operation
• Peer Discovery: Manual connection to other peers using Multiaddr
• System Logging: Structured logging with timestamped system events

Technical Stack

• libp2p: Core peer-to-peer networking (py-libp2p 0.2.9)
• Trio: Async/await framework for concurrent operations
• Textual: Modern terminal user interface framework
• GossipSub: Publish-subscribe messaging protocol
• TCP Transport: Reliable connection transport (QUIC support planned)

Key Components

• main.py - Application entry point with argument parsing
• chatroom.py - Chat room logic and message handling
• headless.py - Background service managing libp2p operations
• ui.py - Textual-based terminal user interface

Usage Examples

# Start with Textual TUI
py-peer --nick "Sumanjeet" --ui

# Connect to specific peer
py-peer --nick "Devs" --connect /ip4/127.0.0.1/tcp/PORT/p2p/PEER_ID

# Headless mode
py-peer --nick "User" --headless

Testing

• ✅ Multi-peer chat sessions tested
• ✅ Peer discovery and connection verified
• ✅ All UI modes functional
• ✅ Cross-platform compatibility (Linux/macOS/Windows)

Dependencies

• Python 3.12+
• All dependencies managed via pyproject.toml with uv.lock for reproducible builds

Documentation

• Comprehensive README with installation, usage, and troubleshooting
• Architecture diagrams and component descriptions
• Screenshot of working Textual UI interface

Additional Notes

• Uses TCP transport currently; QUIC support may be added in future
• Follows Python best practices with type hints and async patterns
• Modular architecture allows easy extension and customization

[sumanjeet0012]

@seetadev Ready for review