fix: Prevent replaying already solved puzzles across domains

- Add checks in handleGuess, handleSkip, and handleGiveUp to prevent actions on solved/failed puzzles
- Add protection in addGuess to prevent adding guesses to solved puzzles
- Fix and simplify backend state loading logic
- Ensure solved puzzles cannot be replayed when switching domains

components/Game.tsx

@@ -108,6 +108,10 @@ export default function Game({ dailyPuzzle, genre = null, isSpecial = false, max
 
     const handleGuess = (song: any) => {
         if (isProcessingGuess) return;
+        // Prevent guessing if already solved or failed
+        if (gameState?.isSolved || gameState?.isFailed) {
+            return;
+        }
 
         setIsProcessingGuess(true);
         setLastAction('GUESS');
@@ -159,6 +163,9 @@ export default function Game({ dailyPuzzle, genre = null, isSpecial = false, max
     };
 
     const handleSkip = () => {
+        // Prevent skipping if already solved or failed
+        if (gameState?.isSolved || gameState?.isFailed) return;
+        
         // If user hasn't played audio yet on first attempt, start it instead of skipping
         if (gameState.guesses.length === 0 && !hasPlayedAudio) {
             handleStartAudio();
@@ -187,6 +194,9 @@ export default function Game({ dailyPuzzle, genre = null, isSpecial = false, max
     };
 
     const handleGiveUp = () => {
+        // Prevent giving up if already solved or failed
+        if (gameState?.isSolved || gameState?.isFailed) return;
+        
         setLastAction('SKIP');
         addGuess("SKIPPED", false);
         giveUp(); // Ensure game is marked as failed and score reset to 0