Type declaration files missing for csv-stringify/lib/browser/sync

Describe the bug

csv-stringfy 5.6.2

import csvStringify from 'csv-stringify/lib/browser/sync';

doesn't work in TypeScript since the type declarations are missing.

I had to add my own csv-stringify.d.ts:

declare module 'csv-stringify/lib/browser/sync' {
  import { Input, Options } from 'csv-stringify';

  function stringify(input: Input, options?: Options): string;
  export = stringify;
}

To Reproduce

Just try to import 'csv-stringify/lib/browser/sync' in any TypeScript project.

Additional context

Looking at the directory structure of the npm package, it's clear that lib/browser/*.js don't have corresponding .d.ts declaration files.

$ tree node_modules/csv-stringify/
node_modules/csv-stringify/
├── CHANGELOG.md
├── LICENSE
├── README.md
├── lib
│   ├── browser
│   │   ├── index.js
│   │   └── sync.js
│   ├── es5
│   │   ├── index.d.ts
│   │   ├── index.js
│   │   ├── sync.d.ts
│   │   └── sync.js
│   ├── index.d.ts
│   ├── index.js
│   ├── sync.d.ts
│   └── sync.js
└── package.json

Start by comparing lib/browser/sync.js and lib/browser/index.js with the existing lib/sync.d.ts and lib/es5/sync.d.ts files. Reproduce the TypeScript import from the issue, then add the missing browser declarations and verify that both browser entry points can be imported without a declaration error.