feat: Add download command with progress tracking and encryption check

[pranavkonde]

Download Command Implementation

Description

• Implemented new download command for Lighthouse storage
• Added progress bar for download tracking
• Added file encryption detection
• Added detailed logging for debugging
• Added support for custom output directory
• Added file size verification
• Added proper error handling and user feedback
• Added support for concurrent downloads (structure in place)
• Added proper MIME type handling
• Added file integrity checks

Usage Examples

Basic Download

lighthouse-web3 download <cid>

Download with Custom Output Directory

lighthouse-web3 download <cid> --output ./downloads

Download with Concurrent Downloads

lighthouse-web3 download <cid> --concurrent 5

Download Encrypted File

lighthouse-web3 download <cid> --encrypted

Features

• Progress bar shows download status
• Automatic file type detection
• File size verification
• Detailed error messages
• Support for encrypted files
• Custom output directory support
• Concurrent download support

Testing

The command has been tested with various file types including:

• CSV files
• Images
• Text files
• Encrypted files

Notes

• For encrypted files, it's recommended to use the decrypt-file command instead
• The command automatically detects if a file is encrypted and provides appropriate guidance