column: use simplified column string titles for now

even though we will replace this soon, it is still technically
more correct than Timeline(1), etc

src/nav.rs

@@ -249,7 +249,7 @@ pub fn render_nav(col: usize, app: &mut Damus, ui: &mut egui::Ui) -> RenderNavRe
         .returning(app.columns_mut().column_mut(col).router_mut().returning)
         .id_source(egui::Id::new(col_id))
         .show_mut(ui, |ui, render_type, nav| match render_type {
-            NavUiType::Title => NavTitle::new(nav.routes_arr()).show(ui),
+            NavUiType::Title => NavTitle::new(&app.columns, nav.routes_arr()).show(ui),
             NavUiType::Body => render_nav_body(ui, app, nav.routes().last().expect("top"), col),
         });