Craft Web Theme Loader using ChatGPT 4

Requirements User Story As a web app user, I want to choose from multiple available themes — sometimes light, other times dark. Work Order Develop a TypeScript-based API that provides helper functions or classes for building a theme picker in web applications. The API should be framework‑agnostic, therefore give code snippets for Angular app and React app using this API. Functional Requirements Support both light and dark themes. Support more than two themes — at least three themes must be available. Support commonly used prebuilt themes, optionally combined with an app‑specific color stylesheet such as colors.css , with an optional dark‑mode variant like colors-dark.css . Support dynamic switching between themes at runtime. When the same web app/site is opened in another browser tab, the explicitly selected theme should be preserved and applied. Technical Requirements Reusable across multiple applications. Minimal API surface to ensure easy customization and easy usage. Neutral with r