* fix(resilience): keep combo quality and auth reasons separate and redact connection labels in terminal errors (#10314)
* fix(resilience): sanitize identifiers in error text, add explicit terminal-status policy, fix classifier ordering (#10314)
Four gaps in the prior combo-error-aggregation fix:
- formatComboOutcomes() only redacted connection identifiers in the model
label, never in the raw upstream error TEXT — a proxy echoing a
connection/account id back in its error body leaked it into the
client-facing terminal message. Redact both.
- The terminal HTTP status was still `lastStatus` — whichever target
happened to fail last, independent of the other targets' reasons. Add
resolveComboTerminalStatus(): preserve a 4xx only when every eligible
target's failure is genuinely "the request is invalid" (model-class);
a heterogeneous mix (e.g. a quality failure + a sibling's 401) now
normalizes to a 5xx-class status reflecting an infra/provider problem,
never a misleading client error borrowed from an unrelated target.
- classifyComboOutcome()'s ordering had `status === 408 || status >= 499`
checked before `status >= 500`, making the provider branch permanently
unreachable — every real 5xx (500/502/503/504) was silently mislabeled
as "timeout". Fixed to an exact match (408/499) and gave 429 its own
explicit `rate_limit` kind instead of falling into the generic "model"
(request-invalid) bucket by accident.
- Added an integration-level regression driving the real handleComboChat
wiring end-to-end (quality failure + sibling 401, and a success-after-
quality-failure case), not just the pure aggregation helpers.
Updated three pre-existing tests whose assertions encoded the OLD
last-writer-wins contract this fix intentionally supersedes (#8486 Part B
antigravity retryAfter tests, two combo-routing-engine status/message
tests) to the new, more precise contract; verified the underlying #8486
concern (wrong target's retryAfter header) is still honored under the new
status policy.
---------
Co-authored-by: adevwithpurpose <adevwithpurpose@users.noreply.github.com>
