[ENHANCEMENT] MSL Installer

[Nylux]

Describe the problem which requires a new feature.

Installing MSL right now is not very intuitive.

Describe the solution you'd like

MSL should have its own installer.
This can take the form of a .msi, .exe or even a simpler .sfx archive.

Describe alternatives you've considered if any

None

Additional context

Bad installations are one of the biggest issue MSL is facing, and it's making us waste time on something that could be avoided altogether by getting a proper solution in place.

[Nylux]

Inno Setup looks promising.

We could write a .iss file, host it on the repo, and have it compiled through this github action when making a release.
Then we just have to add the resulting setup.exe to the release.

This comes with some customization, we can enforce (or not) the install dir, specify supported architectures and run external scripts.