bugfix: Invalid link and button nesting causing double focus

[TobiasWust]

I saw, that if I tab through the window each Link/Button on the left was focused twiced.

That whas caused, because there's a and a nested. Both were possible focus targets and it's semantically wrong html to nest them.

To fix the issue I used radix-ui's Slot-feature.

Before: Ugly focus inbetween

After: immediatly the pretty focus

[TobiasWust]

I also changed the aria-label of the first menuitem to be the same as the tooltip-text

[TobiasWust]

closing this because of release of v3