add persistent mode label when menu not hovered

src/mesh/api.js

@@ -1231,6 +1231,7 @@ const mode = {
             $(`mode-${key}`).classList.remove('selected');
         }
         $(`mode-${mode}`).classList.add('selected');
+        $('mode-label').innerText = mode;
         api.mode.check();
         mesh.edges?.end();
         if (mode === 'sketch') {

src/mesh/build.js

@@ -451,7 +451,8 @@ function ui_build() {
                 menu_item('Surface', mode.surface, '4', 'mode-surface'),
                 menu_item('Face', mode.face, '5', 'mode-face'),
                 menu_item('Edge', mode.edge, '6', 'mode-edge'),
-            ])
+            ]),
+            div({ id: "mode-label" })
         ]),
         div({ class: "menu sketch-on" }, [
             div('Object'),