Update ChestShopSign for better metadata handling

ChestShopSign metadata handling has been improved by encapsulating the sign update within the validity check. The method for updating the sign display has also been restructured to firstly fetch the relevant ChestShopMetaData before proceeding, providing a more efficient processing order.

src/main/java/com/Acrobot/ChestShop/Signs/ChestShopSign.java

@@ -131,11 +131,17 @@ public static boolean isChestShop(Sign sign) {
             return true;
         }
 
-        return sign.getPersistentDataContainer().has(METADATA_NAMESPACED_KEY, PersistentDataType.STRING);
+        boolean isChestshop = sign.getPersistentDataContainer().has(METADATA_NAMESPACED_KEY, PersistentDataType.STRING);
+        if (isChestshop) {
+            updateSignDisplay(sign);
+        }
+
+        return isChestshop;
     }
 
-    private static void updateSignDisplay(ChestShopMetaData chestShopMetaData, Sign sign) {
+    private static void updateSignDisplay(Sign sign) {
 
+        ChestShopMetaData chestShopMetaData = getChestShopMetaData(sign);
         UUID owner = chestShopMetaData.getOwner();
         String fullOwnerName = NameManager.getFullNameFor(owner);
 
@@ -153,10 +159,7 @@ public static ChestShopMetaData getChestShopMetaData(Sign sign) {
             YamlConfiguration yamlConfiguration = new YamlConfiguration();
             yamlConfiguration.loadFromString(string);
 
-            ChestShopMetaData chestShopMetaData = (ChestShopMetaData) yamlConfiguration.get("metadata");
-            updateSignDisplay(chestShopMetaData, sign);
-
-            return chestShopMetaData;
+            return (ChestShopMetaData) yamlConfiguration.get("metadata");
 
         } catch (Exception e) {
             Bukkit.getLogger().log(Level.WARNING, "Exception loading Chestshop Metadata (" + sign.getX() + " " + sign.getY() + " " + sign.getZ() + ").", e);