resolves #396
resolves #135

The rollup-plugin-dts conflicts with @rollup/plugin-commonjs:

The plugin does its own import resolution through the typescript compiler, and usage together with other resolution plugins, such as node-resolve can lead to errors and is not recommended.
rollup-plugin-dts - what-to-expect

I'm not sure if it's okay to simply remove @rollup/plugin-commonjs when generating declarations. 🤔
I've tested some common cases, and it's working fine.