5969ea1558
OpenCode Go and Zen serve muse-spark* only on /v1/responses. Hermes was sending /chat/completions, which returns HTTP 503 with an empty assistant message. Match the published endpoint table and the existing gpt-* routing. - Route muse-spark* to codex_responses on opencode-go and opencode-zen - Add regression assertions next to the gpt-5.6-luna cases