Use flatpak info -l to auto-discover Flatpak installation path

[cyrneko]

📝 Provide a description of the new feature

Spicetify currently requires manual setup to be used with Flatpak, primarily due to the app being installed in different places depending on whether it's per-user or system-wide.

The Spicetify CLI should use the flatpak info -l command to discover the current Spotify installation directory. Data is returned simply as a string pointing to the current commit like this:

~ ❯ flatpak info -l com.spotify.Client
/var/lib/flatpak/app/com.spotify.Client/x86_64/stable/8c89d7ad6a8fa91bacda2f9f5a5d488f70d0d6acbd3773ba3f48f6e53b90a89f

It can then omit the last path (the commit) and replace it by active, adding the rest of the expected path (files/extra/share/spotify/) and use it as the spotify_path

➕ Additional Information

N/A

[rxri]

We don’t want to execute commands unless necessary (for example in the case of Windows Microsoft Store version). I’m pretty sure we have all paths where flatpak version can be.