Feat: demo songs

src/views/options_view.rs

@@ -249,6 +249,12 @@ pub fn render(frame: &mut Frame, app: &App, link: &LinkState, area: Rect) {
                 focus == OptionsFocus::ResetOnboarding,
                 &theme,
             ),
+            render_option_line(
+                "Demo on startup",
+                if app.ui.load_demo_on_startup { "On" } else { "Off" },
+                focus == OptionsFocus::LoadDemoOnStartup,
+                &theme,
+            ),
         ]);
     }
 
@@ -358,6 +364,7 @@ fn option_description(focus: OptionsFocus) -> Option<&'static str> {
         OptionsFocus::MidiInput2 => Some("MIDI input device for channel group 3"),
         OptionsFocus::MidiInput3 => Some("MIDI input device for channel group 4"),
         OptionsFocus::ResetOnboarding => Some("Re-enable all dismissed guide popups"),
+        OptionsFocus::LoadDemoOnStartup => Some("Load a rotating demo song on fresh startup"),
     }
 }