✨ Set up GitHub Copilot instructions for TypeScript OOP RPG project

[Copilot]

This PR configures comprehensive GitHub Copilot instructions for the rpgDungeonCrawler repository following best practices for AI-assisted development.

Changes Made

📋 GitHub Copilot Instructions (.github/copilot-instructions.md)

Created detailed instructions covering:

• TypeScript OOP Standards: Emphasis on class-based design, proper encapsulation, and interface usage
• Project Structure Documentation: Clear guidance on the lib/, utils/, and future server/ directory organization
• Coding Conventions: Naming standards, error handling, and game-specific implementation patterns
• Development Workflow: Guidelines for adding new features with OOP principles
• Future Considerations: Preparation for Ollama integration and AI-powered game mechanics

🔧 TypeScript Configuration

• Added proper tsconfig.json extending the existing base configuration
• Fixed Node.js type definitions and module resolution
• Ensured clean builds with npm run build

📁 Updated .gitignore

• Refined build artifact exclusions while preserving necessary configuration files
• Properly handles TypeScript compilation outputs

Key Features of the Copilot Instructions

The instructions emphasize the project's OOP architecture:

// Example class structure encouraged by the instructions
export class ExampleGameEntity implements ExampleInterface {
    private _privateProperty: string;
    protected protectedProperty: number;
    
    constructor(initialValues: ExampleConstructorInterface) {
        // Proper initialization
    }
    
    public performAction(): void {
        // Clean method implementation
    }
}

The instructions provide clear guidance for:

• Game Mechanics: Dungeon generation, character systems, and item management
• Code Organization: Proper separation between lib classes and shared utilities
• Future Development: Scaffolding for server-side AI integration with Ollama

Verification

• ✅ TypeScript builds successfully without errors
• ✅ Application starts and displays game menu correctly
• ✅ All configuration files properly structured
• ✅ Instructions follow GitHub Copilot best practices

This establishes a solid foundation for AI-assisted development while maintaining the project's commitment to clean, object-oriented TypeScript code.

Fixes #3.

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