SDK Needs Capability Indicators for Search Features

QE reported two bug/improvement requests to the SDK team that seems reasonable but perhaps fell through the cracks. In order for the SDKs to be able to return a FeatureNotAvailable exception, we need to see a server capability, or a more precise error would need to be returned. Without this, the user experience isn't great because the error does not make the root cause obvious.

For reference see CBD-5792 & CBD-5793.

I don't think this is necessarily a blocker, but if we do not add the server capabilities before 7.6 ships, the SDKs will never be able to do any better, because there will be no way to throw a better error (e.g., even if we add it in the future, the 7.6.0 version will not have it, so new SDKs would not be able to use it without affecting 7.6.0 users).