Enhanced zoom target selection to better support parent windows in desktop mode and improved menu popup zoom refresh. Updated setup.css to refine layout, scrolling, and visual effects, including better handling for small screen heights and improved sticky footer appearance.
Introduces a multi-step onboarding process for first-time users, including theme selection and default browser setup. Adds setup.html, setup.js, and setup.css for the new UI, updates main.js and preload.js to support onboarding logic and IPC handlers, and adjusts theme-manager.js for correct theme directory resolution.