Add AbstractGameRule.cs & derived classes

PckStudio.Core/GameRule/WorldPosition.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Numerics;
+using System.Text;
+using System.Threading.Tasks;
+using OMI.Formats.GameRule;
+
+namespace PckStudio.Core.GameRule
+{
+    internal sealed class WorldPosition(int x, int y, int z) : AbstractGameRule
+    {
+        private Vector3 _pos = new Vector3(x, y, z);
+        
+        protected override GameRuleFile.GameRule GetGameRule()
+        {
+            var gameRule = new GameRuleFile.GameRule("WorldPosition");
+            gameRule.AddParameters(
+                new GameRuleFile.IntParameter("x", (int)_pos.X),
+                new GameRuleFile.IntParameter("y", (int)_pos.Y),
+                new GameRuleFile.IntParameter("z", (int)_pos.Z)
+                );
+            return gameRule;
+        }
+    }
+}