feat: Add Claude Desktop Extension with Cross-Platform Support

[rinesh]

📋 Summary

This PR adds a comprehensive Claude Desktop Extension that provides the easiest way to use the Kite MCP Server. The extension includes local execution, cross-platform support, and automated release pipeline.

🚀 Key Features

Claude Desktop Extension

• One-click installation via .dxt file
• Local execution - Runs on user's machine for maximum security
• No configuration required - No manual setup or API key management
• Cross-platform support - macOS, Windows, Linux binaries
• Fallback mode - Automatic fallback to hosted server if local binary fails
• Secure session management - Automatic token refresh and persistence

Automated Release Pipeline

• GitHub Actions workflow for automated extension releases
• Cross-platform binary building for all supported platforms
• Version synchronization between git tags and extension manifest
• Automated .dxt packaging with comprehensive validation
• Release notes generation with installation instructions

Enhanced Development Workflow

• Enhanced justfile with extension build commands
• Version synchronization script for consistent versioning
• Build validation and testing integration
• Documentation updates with installation guides

📁 Files Added

Desktop Extension

• desktop-extension-claude/ - Complete extension directory
  • manifest.json - Extension manifest with tool definitions
  • server/index.js - Node.js proxy wrapper
  • server/package.json - Node.js dependencies
  • build-binaries.sh - Cross-platform build script
  • sync-version.sh - Version synchronization script
  • README.md - Comprehensive extension documentation

Automation & CI/CD

• .github/workflows/release-extension.yml - Automated release workflow
• .github/RELEASE_TEMPLATE.md - Release template for consistency

Development & Documentation

• Enhanced justfile with extension commands
• Updated README.md with extension information
• CLAUDE.md - Project documentation for Claude Code

🔧 Architecture

The extension uses a hybrid proxy architecture:

1. Node.js Proxy - Handles MCP protocol communication
2. Local Binary Execution - Spawns platform-specific Go binary
3. Secure Authentication - Browser-based authentication flow
4. Fallback Mode - Automatic fallback to hosted server
5. Session Management - Persistent session with auto-refresh

📦 Installation

For Users (After Release)

1. Download .dxt file from releases
2. Install via Claude Desktop Settings → Extensions
3. Authenticate via browser when first used

For Developers

# Build extension
just build-extension

# Package extension
just package-extension

# Create automated release
just release-extension 1.0.0

🧪 Testing

The extension includes comprehensive testing:

• Cross-platform binary building validation
• Extension packaging verification
• Authentication flow testing
• Fallback mode testing

🔐 Security

• Local execution - No data transmission in primary mode
• Secure authentication - Browser-based authentication flow
• No stored credentials - No API keys stored locally
• Encrypted session storage - OS keychain integration
• HTTPS-only communication - All network traffic encrypted
• Input validation - Comprehensive request validation

🎯 Benefits

1. Easier onboarding - One-click installation vs manual configuration
2. Enhanced security - Local execution vs hosted server dependency
3. Better user experience - GUI installation vs JSON configuration
4. Automatic updates - Extension updates vs manual server updates
5. Cross-platform consistency - Unified experience across all platforms

📋 Checklist

• Desktop extension implementation
• Secure authentication flow
• Cross-platform binary building
• Automated release pipeline
• Comprehensive documentation
• Enhanced development workflow
• README updates with extension info
• Version synchronization system
• Security validation and testing

🤝 Contributing

This PR maintains backward compatibility while adding the new extension option. The existing HTTP, SSE, and stdio modes remain unchanged and fully functional.

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This contribution significantly enhances the accessibility and security of the Kite MCP Server by providing a user-friendly desktop extension with local execution and automated release infrastructure.