HAL4RT — The definition of interfaces of Surface Layer

In the definition of interfaces of Surface Layer, that are implemented on Surface App, both a set of methods for Application Base and another set of methods for Device Layer are defined in a same interface.
For example, in the definition of System Interface, ‘get_error_detail()’ should be exposed only to Application Base, on the other hand, ’notify_error()’ should be exposed only to Device Layer.
Those methods should be defined in two different interfaces to avoid inappropriate exposure.