Migrate to TypeScript and modernize build tooling

[codeKonami]

Summary

This PR modernizes the poker hand evaluator by migrating the codebase from JavaScript to TypeScript, replacing the webpack/babel build system with Vite, and updating the test framework from Jest to Vitest.

Key Changes

• Language Migration: Converted all source files from JavaScript to TypeScript with full type safety

  • src/pokerhand.js → src/poker-hand.ts with proper type annotations
  • Utility modules reorganized into src/evaluate/ directory with typed implementations
  • Added comprehensive type definitions in src/types.ts (HandRank and CompareResult enums, card types)

• Build System Modernization:

  • Replaced webpack + babel with Vite for faster builds and better ES module support
  • Updated package.json to export both ESM and CommonJS formats with proper entry points
  • Added TypeScript configuration with strict mode enabled
  • Removed old build configuration files (webpack.config.js, .babelrc)

• Testing Framework: Migrated from Jest to Vitest

  • Updated all test files to use Vitest syntax and imports
  • Tests now use ES module imports instead of CommonJS requires

• Code Organization:

  • Consolidated lookup tables into src/tables/ directory with TypeScript exports
  • Separated concerns: evaluate/card.ts, evaluate/validate.ts, evaluate/rank.ts, evaluate/evaluate.ts
  • Added src/bench.ts as TypeScript replacement for the benchmark script

• API Improvements:

  • compareWith() now returns typed CompareResult enum instead of magic numbers (1, 2, 3)
  • getRank() returns typed HandRank enum instead of string literals
  • Better error handling with more descriptive validation messages
  • Added src/index.ts as clean public API export

• HTML/Demo Updates:

  • Updated index.html to use ES module imports
  • Improved HTML semantics (added lang attribute, self-closing tags)
  • Updated demo to use typed CompareResult enum for result comparison

• Development Experience:

  • Added npm run dev for local development with Vite
  • Added npm run bench for running benchmarks with tsx
  • Added npm run test:watch for watch mode testing

Notable Implementation Details

• Maintained full backward compatibility with the Cactus Kev algorithm implementation
• All lookup tables remain unchanged, only converted to TypeScript exports
• Type-safe card validation with literal types for Rank and Suit
• Proper TypeScript strict mode compliance throughout

https://claude.ai/code/session_015nKLAdA1Gva9Yg4Rnfu2vR