Remove the placeholder tiles and the settings tile, fix the mobile header width. iconUrl/formatPlaytime move to utils/games.js (599 min now shows 10h, not 10.0h), and the sync button logic to the useForceSync hook shared with the library.
Header links to Dashboard, Library and Settings. The logo, the login page and
the landing page lead logged-in users to the dashboard. Expired tokens are
removed, and a 403 on the dashboard logs out. Remove the dev dummy token.
Introduce LandingPage, LoginPage and ImprintPage components and replace the previous inline placeholders in App.jsx. Update App layout and header (branding, language toggle, dark mode toggle, route wiring) and use new i18n keys (IMPRINT and LOGIN) in en/de locales. Add client-side validation and UI for the login form. Remove unused assets/icons (public/icons.svg, src/assets/hero.png, vite.svg, vue.svg). Small logging/message tweaks and various Tailwind styling refinements.
Introduce internationalization and basic routing: add i18n initialization (src/i18n.js), translation files (public/i18n/en.json, de.json), and wire i18n into the app (import in main.jsx). Update App.jsx to use react-router (BrowserRouter, Routes) and react-i18next (useTranslation), provide simple Landing/Login/Imprint pages, a language toggle and a dark-mode toggle. Add dependencies in package.json (i18next, i18next-http-backend, react-i18next, react-router-dom) and small Tailwind style tweak (custom-variant for dark) in src/style.css.