Feature request: rollup usage

I've recently switched to Svelte from React. In the Svelte world, rollup seems to be the preferred bundler.
There is no equivalent to `workerize-loader` in rollup.
Would it be possible to make a version that would work with rollup?

首先檢視現有的 workerize-loader webpack 整合，以及 Rollup 的整合進入點。完成的標準是明確定義一個相容於 Rollup 的等效方案，並確立其預期用法與驗證方式。

由索引模型根據 Issue 內容生成。