feat(wallpaper): add apply_wallpaper workflow and rotation worker

Adds a new apply_wallpaper command and its plumbing across
desktop, mobile, and Android. A WorkManager-based rotation
worker handles applying wallpapers in the background. Wallpaper
state now tracks currentId and imageIds for precise control.

- Introduced apply_wallpaper command across desktop, mobile and Android
- Added WorkManager-based rotation worker to apply wallpapers in the
  background
- Extended wallpaper state with currentId and imageIds and updated schemas/permissions

plugins/src/commands.rs

@@ -71,6 +71,10 @@ pub(crate) async fn set_interval<R: Runtime>(app: AppHandle<R>, minutes: usize)
 pub(crate) async fn next_wallpaper<R: Runtime>(app: AppHandle<R>) -> Result<WallpaperState> {
     app.wallpaper().next_wallpaper()
 }
+#[command]
+pub(crate) async fn apply_wallpaper<R: Runtime>(app: AppHandle<R>, id: String) -> Result<WallpaperState> {
+    app.wallpaper().apply_wallpaper(ApplyWallpaperRequest { id })
+}
 
 #[command]
 pub(crate) async fn get_immich_connection<R: Runtime>(app: AppHandle<R>) -> Result<ImmichConnection> {