Add copyright and licensing comments

Added copyright notice and licensing information.

Author: slekkala1

examples/interactive_agent_cli.py

@@ -1,4 +1,9 @@
 #!/usr/bin/env python3
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
 """Interactive CLI for exploring agent turn/step events with server-side tools.
 
 Usage: