Database implement fast switch between Mob and ItemDB

Suggestions
1

Imported from legacy Flarum.
Original author: Siocane (Flarum #11)

e.g. make “Monsters” clickable and next to it “Items”

2

Imported from legacy Flarum.
Original author: Willi (Flarum #7)

We maybe comeback to that later, after bringing new layout/functions to homepage.