feat: add searxng web-search provider, openrouter cost balance UI, offline scripts; update source-launch and docs

docs/subsystems/web.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write docs/subsystems/web.md
-web.md: 3bcd3ac24927c8c51baeabd770e2bd91c5ad1b77
-web.zh.md: 3348be2b808dc286364f5a795b236cb299acd6a6
+web.md: 1d5f9bb5fa4dd12673a379f1d495b0f578183ef8
+web.zh.md: 38b9d5da9a4685adeb5db83e7d0ee895ae2ce013

docs/subsystems/web.md

@@ -2,7 +2,7 @@
 
 English | [中文](web.zh.md)
 
-The web access seam — a [capability seam](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md) that spans **two operations** (search and fetch) on one `ctx.web` service, split across packages: Service Definition ([dsh-web](../../packages/web/web), `ctx.web` + the provider registries), Service Providers ([dsh-web-search-exa](../../packages/web/web-search-exa), [dsh-web-search-perplexity](../../packages/web/web-search-perplexity), [dsh-web-search-deepseek](../../packages/web/web-search-deepseek), [dsh-web-fetch-http](../../packages/web/web-fetch-http)), and Consumer ([dsh-tool-web](../../packages/web/tool-web), the `web_search`/`web_fetch` tool schemas). Web is **one optional capability**, not part of the agent-loop spine — so its vocabulary lives here, not in [core.md](core.md). A search-provider swap does not change how the model asks for a query, and a fetch-provider swap does not change how the model asks for a URL.
+The web access seam — a [capability seam](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md) that spans **two operations** (search and fetch) on one `ctx.web` service, split across packages: Service Definition ([dsh-web](../../packages/web/web), `ctx.web` + the provider registries), Service Providers ([dsh-web-search-exa](../../packages/web/web-search-exa), [dsh-web-search-searxng](../../packages/web/web-search-searxng), [dsh-web-search-perplexity](../../packages/web/web-search-perplexity), [dsh-web-search-deepseek](../../packages/web/web-search-deepseek), [dsh-web-fetch-http](../../packages/web/web-fetch-http)), and Consumer ([dsh-tool-web](../../packages/web/tool-web), the `web_search`/`web_fetch` tool schemas). Web is **one optional capability**, not part of the agent-loop spine — so its vocabulary lives here, not in [core.md](core.md). A search-provider swap does not change how the model asks for a query, and a fetch-provider swap does not change how the model asks for a URL.
 
 Source: [`packages/web/web/src/types.ts`](../../packages/web/web/src/types.ts)
 

docs/subsystems/web.zh.md

@@ -2,7 +2,7 @@
 
 [English](web.md) | 中文
 
-Web 访问 seam 是一个[能力 seam](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md)，在同一个 `ctx.web` 服务上横跨**两项操作**（search 与 fetch），并拆分到多个包：Service Definition（[dsh-web](../../packages/web/web)，`ctx.web` + 提供方注册表）、Service Provider（[dsh-web-search-exa](../../packages/web/web-search-exa)、[dsh-web-search-perplexity](../../packages/web/web-search-perplexity)、[dsh-web-search-deepseek](../../packages/web/web-search-deepseek)、[dsh-web-fetch-http](../../packages/web/web-fetch-http)）与 Consumer（[dsh-tool-web](../../packages/web/tool-web)，即 `web_search`/`web_fetch` 工具 schema）。Web 是**一项可选能力**，不属于 agent loop（智能体循环）主干，因此其词汇定义在此而非 [core.md](core.md) 中。更换 search 提供方不会改变模型提交查询的方式，更换 fetch 提供方也不会改变模型请求 URL 的方式。
+Web 访问 seam 是一个[能力 seam](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md)，在同一个 `ctx.web` 服务上横跨**两项操作**（search 与 fetch），并拆分到多个包：Service Definition（[dsh-web](../../packages/web/web)，`ctx.web` + 提供方注册表）、Service Provider（[dsh-web-search-exa](../../packages/web/web-search-exa)、[dsh-web-search-searxng](../../packages/web/web-search-searxng)、[dsh-web-search-perplexity](../../packages/web/web-search-perplexity)、[dsh-web-search-deepseek](../../packages/web/web-search-deepseek)、[dsh-web-fetch-http](../../packages/web/web-fetch-http)）与 Consumer（[dsh-tool-web](../../packages/web/tool-web)，即 `web_search`/`web_fetch` 工具 schema）。Web 是**一项可选能力**，不属于 agent loop（智能体循环）主干，因此其词汇定义在此而非 [core.md](core.md) 中。更换 search 提供方不会改变模型提交查询的方式，更换 fetch 提供方也不会改变模型请求 URL 的方式。
 
 源码：[`packages/web/web/src/types.ts`](../../packages/web/web/src/types.ts)