Refactor process tracking to handle null slots and compact array

DD2Switcher/Program.cs

@@ -120,14 +120,32 @@ internal static class Program {
   }
 
   private static void Track(Process process) {
+    // First find the first null slot
+    int firstNullIndex = -1;
     for (int i = 0; i < NumProc; i++) {
       if (windows[i] == null) {
-        windows[i] = process;
-        Console.WriteLine(
-            $"Added {process.ProcessName} to tracked windows at index {i}");
-        return;
+        firstNullIndex = i;
+        break;
       }
     }
+
+    if (firstNullIndex == -1) {
+      Console.WriteLine("No slots available for tracking");
+      return;
+    }
+
+    // Compact the array by shifting non-null elements to the left
+    for (int i = firstNullIndex + 1; i < NumProc; i++) {
+      if (windows[i] != null) {
+        windows[firstNullIndex] = windows[i];
+        windows[i] = null;
+        firstNullIndex++;
+      }
+    }
+
+    // Add the new process at the first null slot
+    windows[firstNullIndex] = process;
+    Console.WriteLine($"Added {process.ProcessName} to tracked windows at index {firstNullIndex}");
   }
 
   private static void TrackWows() {