Explain A1001 in a more actionable way

What does this MR do and why?

I noticed that the explanation of the A1001 error on the Duo Chat page is a bit misleading and causes people to spend a lot of time debugging. Example from Slack (internal).

This error has many causes. We are working to break it up into multiple errors. For now though, there's not much that the customer can do to debug it on their end.

MR acceptance checklist

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