Say "component" for the component

"Embedded" already means something here: the embedded package is the
widget build. Where a comment meant Element Call running as a React
component inside a host application, it now says so, and the params it
starts from are `componentProperties`. "Host" stays the word for the
application on the other side, whether that is a widget container or an
application rendering the component.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

component/build/scopeStylesToRoot.ts

@@ -41,7 +41,7 @@ const IS_ROOT = `:where(${ROOT_SELECTOR})`;
  *
  * As a page of its own, Element Call can style the document: normalize.css and
  * Compound speak of `html`, `body` and bare elements, and the design tokens are
- * declared on `:root`. Embedded in a host, all of that would land on the host's
+ * declared on `:root`. As a component, all of that would land on the host's
  * document too. This rewrites every selector so that it matches only the root
  * or its descendants:
  *