So, let's get straight to the point.
We both have a Windows computer, so even if I switch to Linux(not yet, I need to give my PC, maybe by Saturday, I hope so), you can test Windows. We know that Mac and Linux use the bash shell. Well, Mac uses Zsh, but the set of commands are awfully similar.
So, this is my idea. If the shell works, it could mean that the OS build also would work.
About the .App Mac executable, we'll see about that later, we can NOT access the runtime that GitHub Actions uses to upload the build.
So, we need a build converter of sorts. I can run only server VMs, so we could run a VM or we could try finding any Mac runtimes on the cloud.
Here's about the build issue(I need to stop diverting the topic):
Windows works
Linux must be working, I'll check Raspbian(PS: It's Debian, not Ubuntu)
Mac, we must inspect.
For the Mac App file, we must inspect that.
Linux AppImage file needs to be created.
An installer file must be made, where the modules are installed automatically. We could use the .BAT file for Windows(DOS coding 😎) or .SH coding for Mac and Linux.
So, the installer is done, it will build the program from source so users don't miss anything.
About the runtime, remove Windows and Mac. Let Linux be there, once we find a Mac fix, we can add a separate build file for Mac. You can manage Windows, it's a matter of five minutes to build.
If I am confusing enough, I'm sorry. Got a whole lot of things around me, this one dominating them.