docs: define a seam as the (Service, Service provider, Consumer) trio

packages/web/web/README.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 packages/web/web/README.md
-README.md: 73765fe060cc0a2b0fa3d69703a670f488a29ac9
-README.zh.md: bebdb52d6c9bd33db5a982c1f278e71c1882f2de
+README.md: c05965478a049b4145a94075e42bd9602675628f
+README.zh.md: 686157cc87ff456ccc535e3f92fd6524758b35f4

packages/web/web/README.md

@@ -2,7 +2,7 @@
 
 English | [中文](README.zh.md)
 
-The **web access seam**: an abstract `WebService` (`ctx.web`) defining WHAT web access the harness has — search the web, fetch a URL — over multiple providers, without binding the model contract to one vendor's API shape.
+The **`WebService`** (`ctx.web`) defines WHAT web access the harness has — search the web, fetch a URL — over multiple providers, without binding the model contract to one vendor's API shape.
 
 This package is the interface third of the web capability. Unlike bash/fs it spans two capabilities (search and fetch) on one seam, with potentially multiple providers each:
 

packages/web/web/README.zh.md

@@ -2,7 +2,7 @@
 
 [English](README.md) | 中文
 
-**web 访问 seam**：抽象 `WebService`（`ctx.web`）定义 harness 具备哪些 web 访问能力（搜索 web、抓取 URL），并通过多个提供方实现，不把模型约定绑定到某个厂商的 API 形状。
+**`WebService`**（`ctx.web`）定义 harness 具备哪些 web 访问能力（搜索 web、抓取 URL），并通过多个提供方实现，不把模型契约绑定到某个厂商的 API 形状。
 
 该包是 web 能力中负责接口的三分之一。与 bash/fs 不同，它在一个 seam 上跨越搜索与抓取两种能力，每种能力都可能有多个提供方：