Migrate to TypeScript

Migrate JavaScript project to TypeScript with comprehensive type safety: $ARGUMENTS

Current JavaScript State

• Project structure: @package.json (analyze JS/TS mix and dependencies)
• JavaScript files: !find . -name "*.js" -not -path "./node_modules/*" | wc -l
• Existing TypeScript: !find . -name "*.ts" -not -path "./node_modules/*" | wc -l
• Build system: @webpack.config.js or @vite.config.js or @rollup.config.js

Task

Systematically migrate JavaScript codebase to TypeScript with proper typing and tooling:

Migration Strategy: Use $ARGUMENTS to specify gradual migration, complete conversion, strict mode, or incremental approach

Migration Process:

1. Environment Setup - TypeScript installation, tsconfig.json configuration, build tool integration
2. Type Definitions - Install @types packages, create custom type declarations, define interfaces
3. File Migration - Rename .js to .ts/.tsx, add type annotations, resolve compiler errors
4. Code Transformation - Convert classes, functions, and modules with proper typing
5. Error Resolution - Fix type mismatches, null/undefined handling, strict mode issues
6. Testing & Validation - Update test files, configure type checking, validate type coverage

Advanced Features: Generic types, mapped types, conditional types, module augmentation, and strict compiler settings.

Developer Experience: Configure IDE integration, debugging, linting rules, and team onboarding.

Output: Fully typed TypeScript codebase with strict type checking, comprehensive IntelliSense, and improved developer productivity.