QPU-Specific Diagnostics

[kalzoo]

Today, we have a diagnostics utility within the SDK that's useful for identifying certain common misconfigurations and user errors.

What's missing are diagnostics relating to execution and results retrieval. These will help users to independently identify and perhaps resolve issues related to network access and authorization for certain QPUs. This should include, for a user-specified QPU ID:

• Can the ISA and calibration program be retrieved?
• Are the direct access endpoint and all accessors reachable and healthy?