fix(providers): keep minimax chat models text-only

docs/concepts/model-providers.md

@@ -266,7 +266,7 @@ Quirks worth knowing:
 
 - **OpenRouter** applies its app-attribution headers and Anthropic `cache_control` markers only on verified `openrouter.ai` routes. As a proxy-style OpenAI-compatible path, it skips native-OpenAI-only shaping (`serviceTier`, Responses `store`, prompt-cache hints, OpenAI reasoning-compat). Gemini-backed refs keep proxy-Gemini thought-signature sanitation only.
 - **Kilo Gateway** Gemini-backed refs follow the same proxy-Gemini sanitation path; `kilocode/kilo/auto` and other proxy-reasoning-unsupported refs skip proxy reasoning injection.
-- **MiniMax** API-key onboarding writes explicit M2.7 model definitions with `input: ["text", "image"]`; the bundled catalog keeps chat refs text-only until that config is materialized.
+- **MiniMax** API-key onboarding writes explicit text-only M2.7 chat model definitions; image understanding stays on the plugin-owned `MiniMax-VL-01` media provider.
 - **xAI** uses the xAI Responses path. `/fast` or `params.fastMode: true` rewrites `grok-3`, `grok-3-mini`, `grok-4`, and `grok-4-0709` to their `*-fast` variants. `tool_stream` defaults on; disable via `agents.defaults.models["xai/<model>"].params.tool_stream=false`.
 - **Cerebras** GLM models use `zai-glm-4.7` / `zai-glm-4.6`; OpenAI-compatible base URL is `https://api.cerebras.ai/v1`.