Use when writing async Tauri v2 commands — deciding when a command should be `async fn`, spawning background tasks that outlive the command via `tokio::spawn` + cloned `AppHandle`, cancellable long-running work with `tokio::select!` + `CancellationToken`, streaming progress via `Channel` instead of
Use when writing async Tauri v2 commands — deciding when a command should be `async fn`, spawning background tasks that outlive the command via `tokio::spawn` + cloned `AppHandle`, cancellable long-running work with `tokio::select!` + `CancellationToken`, streaming progress via `Channel` instead of polling, and avoiding deadlock anti-patterns (std-mutex across `.await`, holding guards across await