Add a Vuetify-powered application shell (Layout.vue) replacing the previous App.vue, including app bar, navigation drawer, theme toggle, footer and localStorage persistence for theme/drawer. Introduce a routesLayout plugin with a Visibility enum and centralized LayoutRoute definitions; add route components (Home, Impressum, Login, 404NotFound) and update the router to build routes from the new layout definitions. Register Vuetify in main.ts and add dependencies (vuetify, @fontsource/roboto, @mdi/font) in package.json; update tsconfig.app.json to include .ts files. Package-lock.json updated accordingly.
Jonas