Title bar: Export button next to Save

The Export dialog had no visible control: the native menu bar that lists
Export… is not installed, so only the command palette reached it. The
quick access row now has an Export button (the existing Export icon)
that opens the export dialog, enabled when a presentation is open.

crates/ui-egui/src/lib.rs

@@ -1299,6 +1299,28 @@ mod tests {
         assert!(size(&mut harness).unwrap_or(f64::MAX) < after, "Ctrl+[ shrinks");
     }
 
+    /// Export… had no visible control: only the command palette reached it.
+    #[test]
+    fn title_bar_export_opens_the_export_dialog() {
+        let mut harness = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+            |ui, app: &mut SlideApp| {
+                app.logic(ui.ctx());
+                app.ui(ui);
+            },
+            SlideApp::new(Session::with_new(), Services::default()),
+        );
+        harness.run_steps(2);
+        assert!(harness.state().dialog.is_none());
+        // Quick access: Home, Save, Export, each 24 points wide with 2 between, from x = 10.
+        let pos = egui::pos2(10.0 + 2.0 * 26.0 + 12.0, ribbon::TITLE_H / 2.0);
+        harness.hover_at(pos);
+        harness.run_steps(1);
+        harness.event(egui::Event::PointerButton { pos, button: egui::PointerButton::Primary, pressed: true, modifiers: egui::Modifiers::NONE });
+        harness.event(egui::Event::PointerButton { pos, button: egui::PointerButton::Primary, pressed: false, modifiers: egui::Modifiers::NONE });
+        harness.run_steps(2);
+        assert_eq!(harness.state().dialog.as_ref().map(|d| d.id.as_str()), Some("export"));
+    }
+
     #[test]
     fn home_needs_an_open_presentation() {
         let mut app = SlideApp::new(Session::new(), Services::default());

crates/ui-egui/src/ribbon.rs

@@ -53,6 +53,9 @@ pub fn title_bar(app: &mut SlideApp, ui: &mut Ui) {
         if icon_toggle(&mut child, Icon::Save, "Save (⌘S)", has_doc, false).clicked() {
             app.save();
         }
+        if icon_toggle(&mut child, Icon::Export, "Export…", has_doc, false).clicked() {
+            let _ = app.run("app.exportDialog", json!({}));
+        }
         if icon_toggle(&mut child, Icon::Undo, "Undo (⌘Z)", enabled(app, "edit.undo"), false).clicked() {
             run(app, "edit.undo", json!({}));
         }