DNP-21-38: Refactor PuzzleState
To move toward a PuzzleState, we folded "guesses" and "multiGuesses" into the same field "guesses". Then we did the same for "actions" (part of dialog puzzles) and combo set → strings. We fixed a test with bad setup, and found a defect with multi-answer puzzles. Next time, we'll fix that, and move PuzzleState to its own entity.