Add Meta-Tags to the system (Favicon / Sharing Image)

I think it would be great to have some more Meta tags, to have a more »finished« system. Currently everything is still quasar default I think.

We can also think about using the meta plugin by quasar to show the current position on the page in the browsertab. https://v1.quasar.dev/quasar-plugins/meta#introduction

I think these changes would have a great impact in the UX without spending too much time on it.