Handle desktop entries exports on `apt install`/`apt remove`

[Mirko Brombin]

Since vso will become the default shell, we have to handle exports from the inside, this way if the user install a package using apt install, any desktop entry related to that package will be exported to the host system.

To achieve this, we can simply wrap the apt command to check if the active shell is vso and call vso export/vso unexport commands after each apt install/apt remove.