Endpoints for adding an app to an appD will often be implementation dependent and should not be required for compliance

[kriswest]

Area of Issue

[x] App Directory

Issue Description:

The AppD spec currently defines a POST endpoint (/<version>/apps) for adding an application to an appD, and in the absence of any clarifying info, this is currently required for compliance with the Standard. However, most interactions with App Directories by Desktop Agents will be focused on the retrieval of application details, meaning that these are the priority for standardisation efforts. Further, particular implementors and users of the standard may have different governance or integration requirements for their appD that may be incompatible with providing that endpoint.

Consider downgrading the requirement of this POST endpoint so that is optional by applying the SHOULD or MAY keywords to it in the specification or remove it entirely.