move backend to subfolder

tanks-backend/TanksServer/Graphics/DrawMapStep.cs

@@ -0,0 +1,19 @@
+using TanksServer.GameLogic;
+
+namespace TanksServer.Graphics;
+
+internal sealed class DrawMapStep(MapService map) : IDrawStep
+{
+    public void Draw(GamePixelGrid pixels)
+    {
+        for (ushort y = 0; y < MapService.PixelsPerColumn; y++)
+        for (ushort x = 0; x < MapService.PixelsPerRow; x++)
+        {
+            var pixel = new PixelPosition(x, y);
+            if (!map.Current.IsWall(pixel))
+                continue;
+
+            pixels[x, y].EntityType = GamePixelEntityType.Wall;
+        }
+    }
+}