docs: add notes on required typescript changes

README.md

@@ -76,6 +76,12 @@ import { createAppAuth } from "@octokit/auth-app";
 </tbody>
 </table>
 
+> [!IMPORTANT]
+> As we use [conditional exports](https://nodejs.org/api/packages.html#conditional-exports), you will need to adapt your `tsconfig.json` by setting `"moduleResolution": "node16", "module": "node16"`.
+>
+> See the TypeScript docs on [package.json "exports"](https://www.typescriptlang.org/docs/handbook/modules/reference.html#packagejson-exports).<br>
+> See this [helpful guide on transitioning to ESM](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c) from [@sindresorhus](https://github.com/sindresorhus)
+
 ### Authenticate as GitHub App (JSON Web Token)
 
 ```js