Bluetooth pairing provides the way for authentication and security practice, thus the application should be notified if the pairing with a specific device was successful or not. The current zephyr Bluetooth stack doesn't have one which can meet this requirement. So, it is better to add a new API to cover this requirement. Thank you!
More discussions about this request can be referred here: https://lists.zephyrproject.org/g/devel/topic/22117716#4763