The probe loop advanced to the next OIDC candidate on any failure, which meant
it could promote a later candidate over an earlier one the SDK would have
stopped at — turning a failure into a success, a worse defect than the one
being worked around. Four distinct cases: a 500 (an outage the SDK surfaces), a
2xx body that will not parse (terminal for the SDK), a network error (which the
SDK propagates outside the browser's CORS case), and a non-JSON media type.
It now continues only where the SDK's own loop does — a 4xx or 502 — and
otherwise returns the original response, leaving the SDK to make the same
request and reach its own verdict. The `content-type` gate is gone entirely,
because the SDK parses a 2xx discovery body whatever media type it carries, so
gating could skip a genuine OpenID provider document and substitute an
RFC-8414-only one from a lower-priority candidate in its place.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UL9retfvAXRgvi6EWk4SY4
Signed-off-by: cliffhall <cliff@futurescale.com>