first commit

Core/Collections/MapPoint.cs

@@ -0,0 +1,9 @@
+namespace Just.Core.Collections;
+
+public readonly struct MapPoint<T>(T value, int x, int y, IMap<T> map)
+{
+    public readonly T Value = value;
+    public IMap<T> Map { get; } = map;
+    public int X { get; } = x;
+    public int Y { get; } = y;
+}