When creating a name for a module, do not use spaces, accented characters such as é, à, ç, ä, ö, ü or special characters such as slashes /, \ and so on.
Magnolia continuously scans the file system folder defined by the magnolia.resources.dir property.
In this case, it looks inside the light-modules folder and registers your module(s) automatically.
It detects new and modified templates, dialogs and (web)resources.
Open the Resource Files app from the Web dev section of the App launcher, and look for the hello-magnolia module structure to confirm it has been registered:
The icon in the Origin column indicates that the resource is loaded from the file system.