next.js

e3688fbd - updated the example of with-three-js to utilize the App Router (#70287)

updated the example of with-three-js to utilize the App Router (#70287) This PR updates the with-three-js example to use the App Router. Here are the changes that have been made: - Renamed the pages folder to the app folder. - Updated the routing for `/`, `/birds` & `/boxes` files to align with the App Router. - Added the `layout.tsx` & `tsconfig.json` file as part of the App Router. - Updated the package.json file. The following actions were performed as part of this PR: - Ran `pnpm prettier-check `with no issues found. - Executed the `pnpm check-examples` script. CC: @samcx --------- Co-authored-by: samcx <sam@vercel.com>