Improve the related tests and code logic with `tsconfig`

I will improve the related tests and code logic in the upcoming PRs. It will be restored in the upcoming PRs.

_Originally posted by @shulaoda in https://github.com/rolldown/rolldown/pull/5882#discussion_r2296837640_
            