Each official settings page now lives in a client package of its own:
`ui-settings-shell`, `ui-settings-agent-loop`, `ui-settings-subagent`
and `ui-settings-web-search` register into `plugins.item` while the Host
serves their namespaces, through the new `settingsScope.whileServed`
watch, each with its own dictionary and styles. The form model, the
fields and the form move to `ui-primitives` as the shared settings kit,
so a community package's browser half builds a page the same way.
`ui-settings-plugins` keeps only the Built-in plugins section shell
around the inventory tab.
The companions hold Loader rows in `web-app` behind the section; the
client catalog, config catalog and module graph regenerate; the
settings-card cookbook walks through a companion package.
Tianyi Cui