Re-implement UI reskin with working legacy toggle

Re-implement UI reskin with working legacy toggle; add return to title option to menu

src/ui/abstact-option-select-ui-handler.ts

@@ -2,7 +2,7 @@ import BattleScene, { Button } from "../battle-scene";
 import { TextStyle, addTextObject } from "./text";
 import { Mode } from "./ui";
 import UiHandler from "./ui-handler";
-import { addWindow } from "./window";
+import { addWindow } from "./ui-theme";
 
 export interface OptionSelectConfig {
   xOffset?: number;