NewSession creates a new session based on the current session type.

MaxRetries is the maximum number of times to retry setting the wallpaper.

CurrentWallpaper is a helper struct for representing the current wallpaper state on displays.

Display represents a display that can use a wallpaper.

Session is a struct for managing the desktop session's wallpaper.

SetWallpaperParams is a struct for setting the wallpaper.

SessionProvider is an interface for interacting with the desktop session.

I expect this would need to change to support more varieties of Wayland compositors and Xorg session types.