Entrypoint in package.json is incorrect.

### Describe the bug

Entrypoint in package.json is incorrect. It should be `express.js `instead of `src/index.js`.

### Expected behavior

Deployment should succeed on vercel with Express.js application preset.

### Screenshots / Live demo link

### Additional context

_No response_

Open package.json and inspect the entrypoint used for the Express.js application preset on Vercel. Compare the configured src/index.js path with the requested express.js entrypoint, then verify that deployment succeeds with the corrected configuration.

Written by the indexing model from the issue text.