This change allows for more general testing of scripted code. Currently our only tests are under simulation/components whereas we should be able to test global scripts, simulation helpers, etc.
This change also uses the opportunity to address a little note in the code and it fixes #4427. It also removes code duplication in the script interface.
Such a limitation currently blocks (by design) #2951. With this I will be able to write scripted tests that are not scoped to a scripted component but to the entire simulation handling of templates.
Beyond the scope of this patch, we should support other mods than the public one, and we could think about a way to test the GUI.