OpenAthens Wayfinder error messages

These are the user messages that could be displayed in Wayfinder (but hopefully will not need to be):

Error message	Cause
Application not found $appId@$domain	One or both of: Invalid application id in the request Invalid domain in the request (Only applies to OpenAthens Keystone)
Could not fetch details for entity : $entityId	Invalid entityID in the request
Invalid return url : $returnUrl	Invalid Return URL
Service unavailable, please try again after some time.	One or more of: sp.openathens.net is unavailable The search index is unavailable The underlying metadata service is unavailable
The discovery request should contain domain with application id	There is no domain / no application ID in the request (Only applies to OpenAthens Keystone)
The discovery request should contain entity ID	There is no entityID in the request