//! Tool-surface registration for `car-engine`.
//!
//! Populated in CD-10 (see docs/CAR_DESKTOP.md). Mirrors the
//! `car-browser::tools::BrowserToolExecutor` shape so the
//! executor's OPA loop treats `desktop_*` and `browse_*` tools
//! identically at the planner level.
//!
//! When CD-10 lands, this module exports a `DesktopToolExecutor`
//! that wraps an `Arc<dyn DesktopBackend>` and registers:
//!   * desktop_list_windows
//!   * desktop_observe
//!   * desktop_capture
//!   * desktop_focus_window
//!   * desktop_click
//!   * desktop_type
//!   * desktop_keypress
//!
//! plus the corresponding ToolSchema definitions and the
//! permission-rule defaults from docs/CAR_DESKTOP.md §
//! "Tool surface".
