754d229bea
_probe_openai_compatible_models kept the FIRST failure, so a server that lives at /v1 and wants a key (root 404, /v1/models 401) reported 'HTTP 404' instead of 'rejected the API key'. A later non-success now replaces a retained 404 and is reported against the candidate that produced it. Also adds the Settings vitest: after Test the URL input shows the base that actually served /models, so deleting the form rewrite goes red (#65488).