Add Applicability Language to Usage Settings

In order to ensure that the API contract is clear, move some
language from proposed CDD language onto the actual API surface
itself to clarify when various usage settings need to be supported.

Bug: 225950273
Test: make offline-sdk-docs (docstring only changes)
Change-Id: Idee297aaf7ac3af7f5fb86d85d806da13011c036