Phase 1 of client-side quota tracking for NVIDIA NIM (no rate-limit
headers, no usage API):
- Register nvidia in PROVIDER_DEFAULT_RATE_LIMITS (40 RPM sliding
window, matching the documented free-tier note), operator-overridable
via a new ResilienceSettings.providerQuotaOverrides map.
- Per-connection concurrency cap (default 6) via a new
nvidiaConcurrencyGate leaf module wrapping rateLimitSemaphore,
wired into DefaultExecutor.execute().
- Per-model 429 lockout: confirmed already satisfied by #6773's
passthroughModels flag on the nvidia registry entry (no new code
needed) — added as a regression-guard test instead.
Phase 2 (AIMD adaptive ceiling learning) and Phase 3 (dashboard quota
card + combo-routing headroom preference) are explicitly deferred to
follow-up issues, per the plan's own scope note.
