[pdfkit] Update type definitions for v0.20.0 breaking changes and new entry points #75529

Description

With the release of PDFKit v0.20.0, several module exports, runtime signatures, and module entry points were added or updated. The current @types/pdfkit definitions cause TypeScript compilation errors when following the official v0.20.0 documentation.

Key Issues & Missing Features

1. Named Exports Missing in Root Module

   • PDFKit v0.20 exports PDFDocument, LineWrapper, registerFile, and registerStdFonts as named exports.
   • Current behavior: @types/pdfkit only exports export = doc, breaking import { registerFile } from 'pdfkit' or named PDFDocument imports.

2. Missing Submodule Declarations

   • pdfkit/output: toBytes(doc) and toBlob(doc) missing.
   • pdfkit/standard-fonts/*: Wildcard imports for standard fonts (import Helvetica from 'pdfkit/standard-fonts/Helvetica') are untyped.

3. Strict AcroForm Options

   • Runtime v0.20 throws errors on unmapped AcroForm options. @types/pdfkit currently uses permissive/unmapped keys (Record<string, any>).

4. Type Signature Updates

   • registerFile, image, and file methods need Uint8Array support.
   • doc.font() should accept parsed fontkit.Font instances.

Minimal Reproduction Example

import { PDFDocument, registerFile } from "pdfkit"; // ❌ Error: Module 'pdfkit' has no exported member 'registerFile'
import { toBytes } from "pdfkit/output";           // ❌ Error: Cannot find module 'pdfkit/output'
import Helvetica from "pdfkit/standard-fonts/Helvetica"; // ❌ Error: Cannot find module 'pdfkit/standard-fonts/Helvetica'

registerFile("fonts/font.ttf", new Uint8Array());
const doc = new PDFDocument();
const bytes = await toBytes(doc);

Proposed Changes Summary

• Update the root module export using a merged namespace/export strategy to support named exports alongside CJS compatibility.
• Add module definitions for pdfkit/output and pdfkit/standard-fonts/*.
• Expand ImageSrc and PDFFontSource to include Uint8Array and fontkit.Font.
• Strictly type AcroFormFieldOptions.