[feature]: Assets from multiple directories

[marcus-pousette]

Is your feature request related to a problem? Please describe. I am trying to create a Web Worker from a script that lives in a dependency, but in order to server this file I somehow need to make it an asset of the polka server. It seems like I now have to copy it into the root directory of the project I want to test to make it work

Describe the solution you'd like I would be great if I somehow could bundle and provide it without having to manually copy the the asset to the same folder as cwd. The --assets command does not do what I expect, it seems to just rewrite where the asset folder is.

Describe alternatives you've considered Make a script that copies the worker scripts into some temp folder that is inside of root folder of the project