SEO optimization using SSG with sitemap.xml for routes

Is your feature request related to a problem? Please describe.
Google- and especially Bingbot can't see the meta html header tags at the moment and the different pages are sometimes not found.

Describe the solution you'd like
All important subpages should be rendered on the server using Server Side Generation (SSG)

Describe alternatives you've considered
Using Server Side Rendering could further improve performance, as the server renders all dynamic content additionally to static content. As performance isn't a problem and we would need an active node server to be running in production this alternative doesn't seem feasible. A first check if it works using vite-ssr wouldn't run because of problems with the PrimeVue imports.

Additional context
Further I would like to set German as the main language for the page, so that the server side generated content is in German. Alternatively the server side rendering could use a different language than the dynamically served version, which could lead to problems during hydration (matching client side content with pre-rendered pages).