Make SolveApp::start honour a command's enabled flag, and disable solid.move inside a sketch (#740)

`SolveApp::start` now honours a command's enabled flag, so shortcuts, the command palette and the control channel can't start a disabled command, and Move is disabled while a sketch is open.

crates/ui-egui/src/control.rs

@@ -137,6 +137,7 @@ pub fn handle(app: &mut SolveApp, ctx: &egui::Context, req: &ControlRequest) ->
             "camera": app.cam,
             "tool": app.tool.as_ref().map(|t| t.cmd),
             "dialog": app.dialog.as_ref().map(|d| format!("{d:?}")),
+            "status": app.status.as_ref().map(|(text, _, error)| json!({"text": text, "error": error})),
             "hover": app.viewport.hover.as_ref().map(|h| format!("{h:?}")),
             "renderer": if app.viewport.gpu.is_some() { "gpu" } else { "cpu" },
             "frame_ms": app.frame_ms,