feat: comprehensive rewrite and modernization of codenames library

[koistya]

Summary

This PR represents a comprehensive rewrite and modernization of the codenames library, transforming it from a basic proof-of-concept into a production-ready TypeScript library with extensive features and documentation.

Key Changes

• Core API Redesign: Refactored to support both default cities-20 word list and custom word lists through a clean, intuitive API
• Comprehensive Test Coverage: Added extensive test suites across all modules, themes, and edge cases
• TypeScript & ESM: Full TypeScript rewrite with proper type definitions and modern ESM exports
• Enhanced CLI: Improved command-line interface with better theme handling, error messages, and default behavior
• Documentation Overhaul: Complete README rewrite with detailed API docs, practical examples, and use cases
• Blog Content: Added comprehensive guide for preview deployments using codenames
• Word List Management: Enhanced generation scripts with proper validation and consistent formatting
• Error Handling: Robust error handling for invalid inputs, edge cases, and boundary conditions

Technical Improvements

• Added SPDX license headers to all source files
• Implemented factory pattern for theme-specific codename functions
• Restructured project with clear separation of concerns (core/, words/, docs/)
• Enhanced hash distribution analysis and validation
• Improved CLI with support for default theme and better error reporting

Files Changed

• 77 files modified with 1,950 additions and 279 deletions
• New core functionality in core/ directory
• Enhanced test coverage across all word lists and functionality
• Comprehensive documentation and examples

Test Plan

• Run bun test to verify all tests pass
• Test CLI functionality with various themes and inputs
• Verify TypeScript compilation and type checking
• Validate word list generation and consistency
• Test error handling for edge cases
• Verify ESM exports work correctly in different environments