[Bug]: The sideEffects package is not working with namespace import.

[Fitz6]

Version

Browsers:
    Chrome: 126.0.6478.127
    Edge: Chromium (126.0.2592.87)
  npmPackages:
    @rsbuild/core: 1.0.0-alpha.6 => 1.0.0-alpha.6

Details

// test.js
export const doSomething = () => {
  console.log('It works.')
}
window.doSomething = doSomething

// index.js with namespace import
import * as something from './test.js'

window.doSomething() // TypeError: window.doSomething is not a function

// index.js with side effect import
import './test.js'

window.doSomething() // It works.

Reproduce link

https://rsbuild.dev/guide/start/quick-start

Reproduce Steps

1. execute rsbuild dev
2. find the error message in the console