Spectator mode needs improvements

[Bios-Marcel]

The spectator mode use a one-turn delay when switching modes. This means it might not be immediately clear what mode you are in (spectating, guessing or pending switch request).

Therefore it would be good if the state was clearly visible somewhere that doesn't require user interaction first. This could potentially go into the toolbox area. As the toolbox is hidden in spectator mode either way. This could be accompanied by a rejoin button in the toolbox. While this would duplicate the button, it might still be useful.

A good way would usually be the lobby header. But this will make it cramped on mobile again.