feat: Intercambiar posiciones de botones de historial y salir

- Botón de salir (casita verde) ahora en top-4 (arriba)
- Botón de historial movido a top-[46px] (debajo)
- Separación de 2px entre ambos botones
- Botones alineados verticalmente en la esquina superior derecha

client/src/components/ExitGameButton.tsx

@@ -20,7 +20,7 @@ export default function ExitGameButton({ onExit, playerName }: ExitGameButtonPro
                 onClick={() => setShowConfirm(true)}
                 whileHover={{ scale: 1.05 }}
                 whileTap={{ scale: 0.95 }}
-                className="fixed top-20 right-0 z-50 bg-gradient-to-l from-green-600 to-green-700 hover:from-green-500 hover:to-green-600 text-white rounded-l-lg px-2 py-3 shadow-lg border-2 border-green-500 border-r-0 transition-all hover:shadow-green-500/50"
+                className="fixed top-4 right-0 z-50 bg-gradient-to-l from-green-600 to-green-700 hover:from-green-500 hover:to-green-600 text-white rounded-l-lg px-2 py-3 shadow-lg border-2 border-green-500 border-r-0 transition-all hover:shadow-green-500/50"
                 title="Volver al lobby"
             >
                 <svg

client/src/components/GameBoard.tsx

@@ -897,7 +897,7 @@ export default function GameBoard({ gameState, currentPlayerId, actions, fullPla
                 {/* HISTÓRICO DE MISIONES (Esquina superior derecha) */}
                 {gameState.missionHistory.length > 0 && (
                     <motion.div
-                        className="fixed top-4 right-0 z-50"
+                        className="fixed top-[46px] right-0 z-50"
                         initial={false}
                         animate={{
                             x: isHistoryCollapsed ? '0%' : '0%'