Fix smoke 1차 follow-up gaps: player resolver, type target, filter, utf8 (#12)

src/Recordingtest.Recorder/Program.cs

@@ -82,6 +82,30 @@ public static class Program
             Console.Error.WriteLine($"[recorder] attach failed: {ex.Message}");
         }
 
+        // Issue #12 Gap C — once attached, drop events that originate from
+        // any window not owned by the SUT process.
+        if (app is not null)
+        {
+            int sutPid = app.ProcessId;
+            hook.Filter = new SutProcessWindowFilter(
+                sutPid,
+                processFromPoint: (x, y) =>
+                {
+                    var hwnd = NativeMethods.WindowFromPoint(new NativeMethods.POINT { x = x, y = y });
+                    if (hwnd == IntPtr.Zero) return 0;
+                    NativeMethods.GetWindowThreadProcessId(hwnd, out var pid);
+                    return (int)pid;
+                },
+                processFromForeground: () =>
+                {
+                    var hwnd = NativeMethods.GetForegroundWindow();
+                    if (hwnd == IntPtr.Zero) return 0;
+                    NativeMethods.GetWindowThreadProcessId(hwnd, out var pid);
+                    return (int)pid;
+                });
+            Console.WriteLine($"[recorder] window filter active for pid={sutPid}");
+        }
+
         var scenario = new Scenario
         {
             Name = System.IO.Path.GetFileNameWithoutExtension(args.OutputPath),