openclaw - 💡(How to fix) Fix feat: Add Xiaomi MiMo Web Search provider

"tools": [{
  "type": "web_search",
  "max_keyword": 3,
  "force_search": true,
  "user_location": {
    "type": "approximate",
    "country": "China",
    "city": "Wuhan"
  }
}]
The model returns synthesized answers with URL citations in the response annotations field.

**API Details**
Docs: https://platform.xiaomimimo.com/static/docs/usage-guide/tool-calling/web-search.md
Supported models: mimo-v2.5-pro, mimo-v2.5, mimo-v2-pro, mimo-v2-omni, mimo-v2-flash
Auth: Same API key as MiMo models (XIAOMI_API_KEY / tp-xxx for Token Plan)
Pricing: ¥25/1K requests (China), $5/1K requests (Overseas)
Prerequisite: Web Search Plugin must be enabled on the MiMo platform (Console → Plugin Management)
**Why**
The existing Xiaomi plugin (extensions/xiaomi) only supports model inference. Users in China (where SearXNG, DuckDuckGo, etc. are blocked) currently have no working web_search provider without a proxy. MiMo Web Search is a natural fit since it's accessible directly from China and users already have the API key configured.

**Proposed Integration**
Provider ID: xiaomi
Plugin: reuse existing xiaomi plugin (no new plugin needed)
Config path: plugins.entries.xiaomi.config.webSearch (optional overrides for max_keyword, force_search, user_location)
The provider should call the MiMo chat completions API with web_search tool and extract citations from the response
**References**
Xiaomi MiMo Web Search docs: https://platform.xiaomimimo.com/static/docs/usage-guide/tool-calling/web-search.md
Existing search provider implementations: extensions/kimi, extensions/minimax