Fix auto play label and first step behavior

- Change initial play button label from Resume to Auto Play
- Ensure first step opens a single box when manually stepping
- Adjust logic to start from an initial idle state (-1) to align with expected behavior

X-Lovable-Edit-ID: edt-70f04cee-2de9-4621-9009-66a571a91a4f

src/components/PresentsPuzzle.tsx

@@ -23,7 +23,7 @@ const PresentsPuzzle = ({
   const [aliceFound, setAliceFound] = useState(0);
   const [bobFound, setBobFound] = useState(0);
   const [isRunning, setIsRunning] = useState(false);
-  const [currentStep, setCurrentStep] = useState(0);
+  const [currentStep, setCurrentStep] = useState(-1);
   const [aliceOrder, setAliceOrder] = useState<number[]>([]);
   const [bobOrder, setBobOrder] = useState<number[]>([]);
   const [winner, setWinner] = useState<'alice' | 'bob' | 'tie' | null>(null);
@@ -406,7 +406,7 @@ const PresentsPuzzle = ({
               className="gap-2"
             >
               <Play className="w-4 h-4" />
-              {currentStep === -1 ? 'Start' : 'Resume'}
+              {currentStep === -1 ? 'Auto Play' : 'Resume'}
             </Button>
             <Button 
               onClick={pauseSimulation}