docs: record the forwarded-event surface and its face boundaries

Each owner package's README states which of its cordis events are forwarded and
that the declaration now lives in the client-safe ./types export. api/remotes
documents the allowlist as the single control point and the deliberate
both-faces listing of src/types.ts; development.md keeps the split-tsconfig rule
current.

packages/settings/settings/README.md

@@ -28,6 +28,8 @@ Subclasses implement `writable`, `load()`, and `persist(ns, section)`, optionall
 
 `settings/document-updated (ns, revision)` fires whenever the RAW user section changes, whether or not the resolved value did. Configuration surfaces need this one: storing an override equal to the composition base leaves the resolved value alone but changes what the document says (the field is now overridden, not inherited) and moves the revision every open editor is holding. Listener containment matches `settings/updated`.
 
+Both declarations live in the client-safe `./types` subpath export, together with the `SettingsNamespace` and `SettingsUpdateSource` types their signatures name; the package root re-exports those types. A consumer outside the Host compilation face therefore reads the very signature the Host emits instead of restating it.
+
 ## Model Experience
 
 Indirectly, through consumer plugins that resolve model-affecting values (for example a default model route) from their namespaces; each consumer's own surface documents the effect.

packages/settings/settings/README.zh.md

@@ -28,6 +28,8 @@
 
 `settings/document-updated (ns, revision)` 在**原始**用户分节发生变化时触发，无论解析值是否随之改变。配置界面需要的是这一个：存入一个与组合 `base` 相同的覆盖值不会改变解析值，却改变了文档的说法（该字段从继承变成了覆盖），也推进了每个已打开编辑器所持有的 revision。监听器的收容方式与 `settings/updated` 相同。
 
+两条声明都住在 client-safe 的 `./types` 子路径出口，与其签名点名的 `SettingsNamespace`、`SettingsUpdateSource` 类型同处一处；包根继续 re-export 这些类型。于是 Host 编译面之外的消费方读到的正是 Host 发射的那一份签名，而不必再写一遍。
+
 ## 模型体验
 
 间接生效：消费插件从各自 namespace 解析影响模型的值（例如默认模型路由）；效果由各消费者自己的文档描述。