fix: transform item logic crash (opentibiabr#2517)

Resolves opentibiabr#2516

Related to: opentibiabr#2419

In the updated version of the code, we streamlined the condition for
item decay by integrating an additional check directly into the initial
if statement. Previously, we had a separate check inside the if block to
determine if the newType.decayTo value was present, which then set the
itemId accordingly. However, this approach had the potential risk of
creating unnecessary complexity and possibly leading to a loop if the
conditions weren't met as expected.

To address this and enhance clarity, we've moved the check for
newType.decayTo into the condition of the if statement itself. This
adjustment ensures that all necessary conditions are evaluated upfront,
making the code more straightforward and preventing the execution from
entering the if block unless all criteria are satisfied. This change not
only simplifies the logic but also ensures that we avoid any unintended
loops by making the transition to the else if statement more predictable
when the initial conditions are not met.

src/game/game.cpp

@@ -2616,12 +2616,10 @@ std::shared_ptr<Item> Game::transformItem(std::shared_ptr<Item> item, uint16_t n
 
 			auto decaying = item->getDecaying();
 			// If the item is decaying, we need to transform it to the new item
-			if (decaying > DECAYING_FALSE && item->getDuration() <= 1) {
+			if (decaying > DECAYING_FALSE && item->getDuration() <= 1 && newType.decayTo) {
 				g_logger().debug("Decay duration old type {}, transformEquipTo {}, transformDeEquipTo {}", curType.decayTo, curType.transformEquipTo, curType.transformDeEquipTo);
-				g_logger().debug("Decay duration new type, decayTo {}, transformEquipTo {}, transformDeEquipTo {}", newType.decayTo, newType.transformEquipTo, newType.transformDeEquipTo);
-				if (newType.decayTo) {
-					itemId = newType.decayTo;
-				}
+				g_logger().debug("Decay duration new type decayTo {}, transformEquipTo {}, transformDeEquipTo {}", newType.decayTo, newType.transformEquipTo, newType.transformDeEquipTo);
+				itemId = newType.decayTo;
 			} else if (curType.id != newType.id) {
 				if (newType.group != curType.group) {
 					item->setDefaultSubtype();