The banner provider branch tested model-name substrings (`/deepseek/`, `/kimi/`,
`/mistral/`, `/llama/`) before aggregator base-URL substrings (`/openrouter/`,
`/together/`, `/groq/`, `/azure/`). When running OpenRouter/Together/Groq with
vendor-prefixed model IDs (e.g. `deepseek/deepseek-chat`, `moonshotai/kimi-k2`,
`deepseek-r1-distill-llama-70b`), the banner mislabelled the provider.
Reorder: explicit env flags (NVIDIA_NIM, MINIMAX_API_KEY) and codex transport
win first; base-URL host checks run before rawModel fallback; rawModel only
fires when the base URL is generic/custom. Add unit tests covering the
aggregator × vendor-prefixed-model matrix plus direct-vendor regressions.
Closes#855
e346b8d5ec