Add support of typescript

[umidjon-2231]

This pull request introduces TypeScript definitions (type.d.ts) for html2pdf.js, allowing developers to use the library with improved type safety and better IDE support.

Changes Included:

• Created a TypeScript declaration file (type.d.ts) with comprehensive type definitions for the library.
• Added typings for Html2PdfOptions, Html2PdfWorker, and Html2PdfStatic.
• Ensured all documented methods and parameters are typed correctly.
• Included JSDoc comments for better documentation.

Motivation & Benefits:

• Enables TypeScript developers to use html2pdf.js with type checking.
• Enhances code editor autocompletion and documentation.
• Reduces potential runtime errors by enforcing correct API usage.

How to Test:

1. Import the library in a TypeScript project:

   import html2pdf from "html2pdf.js";

2. Use the library with the new type definitions:

   const element = document.getElementById("element-to-print");
   html2pdf().from(element).set({ filename: "test.pdf" }).save();

3. Verify that TypeScript recognizes the method signatures and shows relevant hints in an IDE.

Looking forward to feedback and suggestions!

[R1D3R175]

Would love to see this merged! Thanks for your work :)

It seems like the maintainers of this library are busy working on bug fixes. You could consider adding this to DefinitelyTyped!

While waiting for types to be added, I forked your repo and installed it in my project(s) with npm install git+https://github.com/R1D3R175/html2pdf.js. If anyone wants to have types I encourage to either use PR's author fork or create its own fork and then install it via their dependency manager of choice that supports installing via git.

NOTE: I had to move type.d.ts to dist/ and add "types": "dist/type.d.ts" to package.json in order to make TypeScript find the .d.ts file.

[umidjon-2231]

@R1D3R175
Thanks for the feedback and for sharing your solution for using the types in your project! Moving the file and updating package.json is good to know.