Fix TraceManager.currentFrameSize

BauSystem_Main/src/de/steamwar/bausystem/tracer/TraceManager.java

@@ -59,7 +59,8 @@ public class TraceManager {
         return new ArrayList<>(frameMap.getOrDefault(frameID, new ArrayList<>()));
     }
 
-    public static int currentFrameSize(){
+    public static int currentFrameSize() {
+        if (!frameMap.containsKey(currentFrame)) return 0;
         return frameMap.get(currentFrame).size();
     }