Smoke Test issues and documentation

### Operating System

macOS 15.5

### Environment (if applicable)

Chrome 138.0.7204.158

### Firebase SDK Version

11.8.0

### Firebase SDK Product(s)

AI, Functions

### Project Tooling

Smoke test instructions

### Detailed Problem Description

* Follow the instructions at https://github.com/firebase/firebase-js-sdk/blob/main/e2e/smoke-tests/README.md:

`firebase deploy` failed. The workaround was to run `firebase init` and choose `Functions`.

After successfully deploying:

Three test failures with `yarn test:modular`:

and one test failure with `yarn test:compat`:

Both `yarn start:modular` and `yarn start:compat` failed in the browser with CORS errors:

### Steps and code to reproduce issue

[Smoke Test Readme ](https://github.com/firebase/firebase-js-sdk/blob/main/e2e/smoke-tests/README.md)