[ ] 429 should inform how long to wait (if ratelimit headers are set)
[ ] 404 should have a fixed friendly message ~"not available at the moment"
[ ] 401 should have a fixed friendly message ~"you are not authorised to use..."
[ ] 4xx should have a default friendly message ~"the FlowFuse Assistant cannot help with this request" but allow a message to be sent from the assistant service if code === "assistant_service_denied" (permit specific notifications to be generated in the assistant service like "Your trial has ended" or "Please upgrade to use the assistant")
[ ] Default 500 notification of ~"something went wrong"
Description
Part of https://github.com/FlowFuse/security/issues/92
code === "assistant_service_denied"(permit specific notifications to be generated in the assistant service like "Your trial has ended" or "Please upgrade to use the assistant")Epic/Story
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