Two related hardening fixes for auxiliary calls (which include MoA reference
advisors — a pinned-model path where provider fallback is not a meaningful
recovery):
1. Transient-transport retries: the same-provider retry on a connection reset /
timeout / 5xx / 408 was a single attempt, then fallback. For a pinned aux
call a second blip silently loses the call (root of the run2 double-advisor
'Connection error' collapse — a genuine upstream blip). Now retries N times
with exponential backoff, N = auxiliary.transient_retries (default 2 -> 3
total attempts, clamped [0,6]). Compression-on-timeout fast-fail carve-out
preserved.
2. Per-model client-cache isolation: _client_cache_key excluded the model, so
two concurrent auxiliary calls to the same provider/base_url/key but
different models (e.g. an opus + gpt-5.5 MoA fan-out) shared one cache entry
and could race each other's client lifecycle. Model now participates in the
key -> distinct clients, no cross-call races. Same-model reuse unchanged.
- agent/auxiliary_client.py: _transient_retry_count() + backoff loop; model in
_client_cache_key and both call sites.
- hermes_cli/config.py: auxiliary.transient_retries default (2).
- tests: new retry/isolation tests; updated 2 stale-expectation tests to the
corrected behavior (per-model resolve; N-retry escalation).
Backoff base is overridable (_TRANSIENT_RETRY_BACKOFF_BASE) so tests don't sleep.
