Merge origin/master into worktree/web-plugin-config, adapting to ctx.remote.$on

#2201 landed three moves this branch sits on top of. `bindSettingsScope` became
`ctx.settingsScope.bind` on the Settings surface, so the section injects that
service and the Remote face instead of importing a free function; the
`SettingsScope` types moved into the runtime contract module, which is where
this branch's `base`, `user`, and `unset` now live; and the client
`credentials/changed` event became the forwarded owner event
`credentials/updated`, which the web-search card subscribes to through
`ctx.remote.$on`.

The generated module graph crossed mermaid's 1000-edge render guard with this
branch's 14 new edges. The guard doubles again, exactly as it did at 500 — the
graph counts real package edges, and trimming them to fit a renderer default
would make the document lie about the dependency set.

packages/client/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/client/README.md
-README.md: 419a595e4d0b930106348ff3d55be4574d1d2119
-README.zh.md: a60b4ce920603e92acc43496fc22a6b2b1cbfefa
+README.md: 0b4192644f9704aec6ded4a0c5319aa0c55ae47c
+README.zh.md: de66ff9bf3bb8aca9712b509f44635ef60d98e38