[Manasbh]

I work at Keirolabs, so weigh the suggestion accordingly.

改了什么 · What changed

Adds Keirolabs as an optional keyed web-search provider, following the existing Tavily/Exa/Bocha/Zhipu/Keenable pattern. Default stays auto (free search); nothing changes unless a user picks Keirolabs and enters a key.

• src/tools/search.ts: keirolabs in SEARCH_PROVIDERS / KEYED; keyedRequest → POST https://api.keirolabs.cloud/api/v2/keiro with Authorization: Bearer <key>, body { query, maxResults } (≤50). Results map title / url / snippet / publishedDate through the existing source() tidy; an empty publishedDate is dropped. Existing fallback to free search on auth/HTTP failure applies unchanged. Also updated the header comment's list of keyed providers (it was missing Keenable too).
• Settings UI: "Keirolabs" option in the web-search picker; keirolabs added to the settings search keywords (en / zh-CN / ja / ko / ru).
• Test: new keyed-request case in test/web-search.unit.test.ts.

为什么 · Why

Keirolabs serves queries from its own web index, typically in 100 ms – 1 s, with a free tier (30 req/min). That makes it a low-latency keyed option for the agent's web_search, next to the existing ones.

怎么验证的 · How it was verified

• npm run typecheck && npm test (typecheck clean; full suite passes, incl. the new case)
• 改了 README / docs 时跑了 npm run docs:check · not applicable, no README/docs changes
• 界面改动附了浅色和深色截图 · one new <option> in the existing picker, no layout/style change
• 新增依赖或移植代码时更新了 THIRD_PARTY_NOTICES.md · no new dependencies

Also checked live against the real API through SearchService (not mocked): a valid key returns results with backend: "keirolabs"; an invalid key returns 401, is classified as auth (so Settings shows the key-rejected hint) and falls back to free search.