This PR adds a complete "Hello World" extension to the VS Code repository that serves as a comprehensive example and template for VS Code extension development within the main codebase.

Features Added

The Hello World extension includes:

• Two interactive commands:
  • Hello: Hello World - Shows a simple greeting message
  • Hello: Show Workspace Info - Displays current workspace information
• Keyboard shortcut: Ctrl+Shift+H (or Cmd+Shift+H on Mac) for the Hello World command
• Complete TypeScript setup with proper compilation and type checking
• Cross-platform build scripts (build.sh and build.bat)
• Validation script to verify extension functionality
• Basic test structure demonstrating extension testing patterns
• VS Code debug configuration for easy extension development and testing

Extension Structure

extensions/hello-world/
├── src/
│   ├── extension.ts          # Main extension implementation
│   └── test/
│       └── extension.test.ts # Basic test examples
├── out/                      # Compiled JavaScript output
├── media/                    # Extension assets directory
├── package.json              # Extension manifest with commands and keybindings
├── tsconfig.json            # TypeScript configuration
├── extension.webpack.config.js  # Webpack build configuration
├── build.sh/.bat            # Cross-platform build scripts
├── validate.js              # Extension validation script
└── README.md                # Comprehensive documentation

Development Integration

• Added extension to build/gulpfile.extensions.js compilation list
• Created VS Code launch configuration for debugging ("Launch Hello World Extension")
• Follows existing VS Code extension patterns and coding standards
• Includes proper Microsoft copyright headers and MIT licensing

Usage

Developers can use this extension as:

1. Learning resource: Demonstrates core extension concepts like command registration, user interaction, and workspace access
2. Template: Copy and modify for new extension development
3. Testing: Verify extension development environment setup

Testing

To test the extension:

1. Run ./build.sh (or build.bat on Windows) to compile
2. Open VS Code in repository root
3. Go to Debug view (Ctrl+Shift+D)
4. Select "Launch Hello World Extension"
5. Press F5 to start Extension Development Host
6. Use Ctrl+Shift+P and type "Hello" to see commands

This extension demonstrates essential VS Code extension development patterns including command registration, user interaction, workspace access, keyboard shortcuts, proper TypeScript compilation, and extension lifecycle management.

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