add distance moved score

tanks-backend/TanksServer/Models/Scores.cs

@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace TanksServer.Models;
 
 internal sealed record class Scores
@@ -24,10 +26,15 @@ internal sealed record class Scores
 
     public int PowerUpsCollected { get; set; }
 
+    [JsonIgnore] public double DistanceMoved { get; set; }
+
+    public int PixelsMoved => (int)DistanceMoved;
+
     public int OverallScore => Math.Max(0,
         10000 * Kills
         - 1000 * Deaths
         + 100 * PowerUpsCollected
         + 10 * (ShotsFired + WallsDestroyed)
+        + PixelsMoved
     );
 }