Hello!

Let me know if i should have opened this issue on the [pdfjs-dist](https://github.com/mozilla/pdfjs-dist) repo but I though here would fit.

I'm using pdfjs-dist and I'm in need of some more types to be exported. I have no idea how the types end up in the dist-repo but would love to open a PR if only someone could point me in the right direction 😃 Since I was using an older version of pdfjs-dist I realize the only type I need that's not in the type defs in the latest release are _PageViewport_ from _[display/display_utils](https://github.com/mozilla/pdf.js/blob/master/src/display/display_utils.js#L153)_.
} from "../../src/shared/util.js";
import {
  buildGetDocumentParams,
  DefaultFileReaderFactory,
  TEST_PDFS_PATH,
} from "./test_utils.js";
import {
  DefaultCanvasFactory,
  getDocument,
  PDFDataRangeTransport,
  PDFDocumentLoadingTask,
  PDFDocumentProxy,
  PDFPageProxy,
  PDFWorker,
  RenderTask,
} from "../../src/display/api.js";
import {
  RenderingCancelledException,
  StatTimer,
} from "../../src/display/display_utils.js";
import { AutoPrintRegExp } from "../../web/ui_utils.js";
import { GlobalImageCache } from "../../src/core/image_utils.js";
import { GlobalWorkerOptions } from "../../src/display/worker_options.js";
import { isNodeJS } from "../../src/shared/is_node.js";
import { Metadata } from "../../src/display/metadata.js";
describe("api", function () {
  const basicApiFileName = "basicapi.pdf";
  const basicApiFileLength = 105779; 
  const basicApiGetDocumentParams = buildGetDocumentParams(basicApiFileName);
  let CanvasFactory;