#1 /v1/models: the front fanned out to every engine's /v1/models (slow during
generation). It now fetches the full list once from the coderai-system worker
(config-based list_models, off the GPU engines) — added a /v1/models route to the
system app — with a last-good cache and per-engine fallback if the worker is down.

#3 quant status: the models page polled /admin/api/quantize-status (engine) every
5s unconditionally. It now polls only while a quant job is actually running (and
the tab is visible); startQuantize re-arms it. No idle engine hits.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011DDv7BchtZQWsnPG6Jm49m