[toast] Is it possible to augment/extend existing type?

Not sure if this is a bug or a misconfiguration on my part so please move this issue to discussion if the behavior is as expected

I would like to constraint the `type` in Toast actions to only have a few string literals so I have the following type declaration in my `base-ui.d.ts`
```ts
/** biome-ignore-all lint/correctness/noUnusedVariables: safe, only augmenting types */
import '@base-ui-components/react'

declare module '@base-ui-components/react/toast' {
interface ToastObject {
type?: 'default' | 'info' | 'error' | 'success'
}
}
```
But the hints from `toast.add({ type: /**/ })` is still showing as the default `string | undefined`, even though when press the "Go to definition" key from the IDE, the editor shows both the library code and my `d.ts` file, which means the LSP properly picked up my types file