[TASK] add test cases for calling mcdev via cli instead from javascript

[JoernBerkefeld]

as of now, all our tests rely on importing mcdev as a library in a javascript file.
we need to ensure that whats set up in ./lib/cli.js allow all these angles as well.

please create a new test class that aims to test commands in a metadata agnostic way to fixate the status quo in tests.
while doing so, search for any logic holes, as in, if we are testing for something in our current test cases that would not be possible using CLI commands