When an audit fails, display the probable cause to the user

[phacks]

Right now, to troubleshoot failed audits, one must (have access to and) open the admin interface, go through many hoops to find the failed audits, and see its status / follow the WebPageTest link for more info. This is cumbersome, to say the least.

A few ideas on how to implement this:

• If we have a clear error message from WebPageTest (e.g. if the API Key is invalid), then display it (possibly reworded) and add an actionable message like “please check your API key in settings”
• If we don’t have a clear error message but the errors comes from WPT, then display a link to the failed audit for the user to check by themselves
• If the errors happened on Falco’s backend (a mandatory metric is missing, a random bug) then encourage the user to create an issue on the repository?