Support Closing UI Kit Modals via Overlay Click

Currently, all default modals provided by the UI Kit can only be closed through explicit button actions (e.g., close or cancel buttons).

In our application, we follow a UX pattern where modals can also be dismissed by clicking on the overlay (outside the modal content). This behavior is already implemented in our custom modals, and we would like to have the same capability in the UI Kit modals for consistency.