Given that you are already giving users a source code, you also have the option to ship a precompiled Julia distribution that starts the application. When compressed in MSIX, archive, in my experience, gives around 300…400 MB installer, which may or may not be acceptable. This is the approach taken by AppBundler.jl project on which I have expanded in a recent answer: How are non programmers to use Julia Apps - #4 by Janis_Erdmanis
I also encourage the use of QML. LGPL license allows Qt to be used in a dynamical linking context even if the software product is proprietary. Their current strategy is to deprecate LGPL components with GPL ones, which is the only catch one needs to be aware of when using Qt/QML. The bindings in Julia via QML.jl are of superb quality.