Add Config Helper

[onairmarc]

This pull request introduces several enhancements to the package's build process, module exports, and type safety. The most notable changes are the addition of a type-safe config helper, improvements to build output and declaration generation, and updates to module exports for better compatibility.

Build and output improvements:

• The build script in package.json now generates TypeScript declaration files alongside the build output, and updates the main, types, and exports fields to reference the new entry points and type definitions.

Module exports and API enhancements:

• Added a new export for the tsfmt config helper in src/index.ts, making it available as a top-level API.
• Introduced the tsfmt function in src/tsfmt.ts, which provides a type-safe configuration helper for use in tsfmt.config.ts files.

Refactoring and code organization:

• Updated import paths in src/sortPackage.ts to use barrel exports, simplifying internal module references.