Update ACE_EntityIdHelper to support low IDs entity IDs

Map entities such as trees and bushes do not have a high ID. This results in the game engine returning `0x0x` prefixes when ToString is called.

ToInt and FromString have also been updated to use a high ID of 0 when the array only contains a single element.

addons/core/scripts/Game/ACE_Core/Global/ACE_EntityIdHelper.c

@@ -3,24 +3,38 @@ class ACE_EntityIdHelper
 {
 	//------------------------------------------------------------------------------------------------
 	static array<int> ToInt(EntityID id)
-	{
-		return ACE_HexTools.HexStringToInt(ToString(id));
+	{	
+		array<int> bits = ACE_HexTools.HexStringToInt(ToString(id));
+		if (bits.Count() == 1)
+			bits.InsertAt(0, 0);
+
+		return bits;
 	}
 
 	//------------------------------------------------------------------------------------------------
 	static EntityID FromString(string str)
 	{
-		array<int> bits = ACE_HexTools.HexStringToInt(str);
-		if (bits.Count() < 2)
-			return EntityID.INVALID;
-
+		array<int> bits = ACE_HexTools.HexStringToInt(str);		
+		if (bits.Count() == 1)
+			bits.InsertAt(0, 0);
+		else
+			if (bits.Count() > 2)
+				return EntityID.INVALID;
+
 		return EntityID.FromInt(bits[0], bits[1]);
 	}
 
 	//------------------------------------------------------------------------------------------------
 	static string ToString(EntityID id)
 	{
 		// Drop the last three characters, which are " {}"
-		return id.ToString().Substring(0, 18);
+		// Fixed by LRRP, reported upstream: https://github.com/acemod/ACE-Anvil/issues/152
+		string str = id.ToString();
+
+		// Low id items such as trees/bushes end up with this odd format, fix it
+		if (str.StartsWith("0x0x"))
+			return str.Substring(2, str.Length() - 5);
+		else		
+			return str.Substring(0, str.Length() - 3);
 	}
 }