move backend to subfolder

tanks-backend/TanksServer/GameLogic/CollectPowerUp.cs

@@ -0,0 +1,30 @@
+namespace TanksServer.GameLogic;
+
+internal sealed class CollectPowerUp(
+    MapEntityManager entityManager
+) : ITickStep
+{
+    public Task TickAsync(TimeSpan delta)
+    {
+        entityManager.RemoveWhere(TryCollect);
+        return Task.CompletedTask;
+    }
+
+    private bool TryCollect(PowerUp obj)
+    {
+        var position = obj.Position;
+        foreach (var tank in entityManager.Tanks)
+        {
+            var (topLeft, bottomRight) = tank.Bounds;
+            if (position.X < topLeft.X || position.X > bottomRight.X ||
+                position.Y < topLeft.Y || position.Y > bottomRight.Y)
+                continue;
+
+            // this works because now the tank overlaps the power up
+            tank.ExplosiveBullets += 10;
+            return true;
+        }
+
+        return false;
+    }
+}