feat: add game Knights and Knaves by JadAbouHawili

[joneugster]

https://adam.math.hhu.de/#/g/jadabouhawili/knightsandknaves-lean4game/

[TentativeConvert]

Looks neat and thought-through to me. I especially like the conversion table unicode symbols <-> keyboard available in the inventory under definitions.

@JadAbouHawili: World 3, level 1 switches to editor mode, and so do some of the later levels. Is that intended? If not, perhaps fix this first?

[joneugster]

In that case I'll way for @JadAbouHawili to build and upload a version without copilot as discussed an then I'll see that it gets on the front page by tomorrow night. Thanks for the contribution😊

[JadAbouHawili]

Looks neat and thought-through to me. I especially like the conversion table unicode symbols <-> keyboard available in the inventory under definitions.

@JadAbouHawili: World 3, level 1 switches to editor mode, and so do some of the later levels. Is that intended? If not, perhaps fix this first?

Didn't want the user to write have .. := by so I used Template which imposes editor mode, although @joneugster suggested something regarding have which I'm thinking about. I am also reconsidering other things about the game and will make improvements.