refactor client prediction logic and add tolerance levels; implement restartGame function to reset game state without a full reload

cmd/client/web/game.js

@@ -817,6 +817,23 @@ function deleteHighscoreCode(index) {
     loadMyCodes(); // Reload display
 }
 
+// Restart game without reload
+function restartGame() {
+    console.log('🔄 Restarting game...');
+
+    // Reset game state
+    gameStarted = false;
+    gameStarting = false;
+
+    // Return to main menu
+    setUIState(UIState.MENU);
+
+    // Re-enable start buttons
+    enableStartButtons();
+
+    console.log('✅ Game restarted - ready to play again');
+}
+
 // Export functions for WASM to call
 window.showMenu = showMenu;
 window.hideMenu = hideMenu;
@@ -824,6 +841,7 @@ window.updateLeaderboard = updateLeaderboard;
 window.showGameOver = showGameOver;
 window.onGameStarted = onGameStarted;
 window.saveHighscoreCode = saveHighscoreCode;
+window.restartGame = restartGame;
 
 // Initialize on load
 initWASM();