refactor(client): replace the per-field settings preference controller with a namespace settings scope

bindSettingsScope mirrors the Host-side settings owner seam in the browser:
one scope per namespace publishes a snapshot store (status, section value,
revision, writability, host/memory mode), validates sections against the
namespace's serialized wire schema via dsh-client-schema-form, and keeps the
controller's listener-before-read, revisioned serialized writes, latest-wins
publication, conflict recovery, and disposal quiescence. Theme, locale, and
busy-Enter services now take the scope as a constructor collaborator, which
removes the bindPersistence/syncPreference two-phase callback pair and the
defaulted no-op persist writers; hand-written wire guards fall away in favor
of the registered schema. test-runtime gains a stubSettingsScope double.

packages/client/test-runtime/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/test-runtime/README.md
-README.md: 74da8fde7fd9cc3733d2d1ae03dd3d213e4d553e
-README.zh.md: a86b9e469a5632886891628267002a14588afeaa
+README.md: 455d6f564cea2cb8f88165a8bba1047c762d2fb0
+README.zh.md: e292c57c21dde1f7639ce37ee9b65930c6d153ea

packages/client/test-runtime/README.md

@@ -4,7 +4,7 @@ English | [中文](README.zh.md)
 
 jsdom slot test runtime for client feature specs: a real Cordis `Context`, the production `SlotsService` and web-react renderer, assembled around typed session/workspace doubles. Feature suites exercise declaration, registration, scope, store, inject, rendering, updates, and disposal without hand-building the machinery per suite — and without a second implementation of any production logic.
 
-The doubles implement the same outward faces features receive through ctx (`TestSessions implements ISessions`, `TestWorkspaces implements IWorkspaces`; each fixture session is a `FixtureSession implements SessionFace`), so a production face change breaks the bench at compile time instead of silently drifting. Provide-bundle materialization runs the production `SessionProvideChannel` — the one implementation shared with `SessionsService`. Fixtures feed plain data: list rows, conversation snapshots (immer-patched via `updateSnapshot`), projection values, and `ISession`-typed behavior stubs that fail loud when a spec calls an unstubbed verb. The typed `provide()` constrains fakes for declared service names to `Partial` of that service's outward face.
+The doubles implement the same outward faces features receive through ctx (`TestSessions implements ISessions`, `TestWorkspaces implements IWorkspaces`; each fixture session is a `FixtureSession implements SessionFace`; `stubSettingsScope` is a `SettingsScope` with test-driven publications and a write spy), so a production face change breaks the bench at compile time instead of silently drifting. Provide-bundle materialization runs the production `SessionProvideChannel` — the one implementation shared with `SessionsService`. Fixtures feed plain data: list rows, conversation snapshots (immer-patched via `updateSnapshot`), projection values, and `ISession`-typed behavior stubs that fail loud when a spec calls an unstubbed verb. The typed `provide()` constrains fakes for declared service names to `Partial` of that service's outward face.
 
 Local DOM snapshots: `declare(children)` registers an auto frame whose per-key `<div data-slot>` wrappers are snapshot roots; `renderSlot(key, owner)` returns the slot-local view (container, scoped Testing Library queries, in-place `update(owner)`); a registered snapshot serializer folds CSS-module class hashes (`_frame_a1b2c3` → `frame`) to keep `.snap` files structural and collapses `<svg>` internals to a `data-content` fingerprint. Suites needing a custom page frame use `root.declare(children, Frame)` instead; `mount(plugin)` runs a real fiber with fail-loud service prechecks, and `dispose()` tears down views, feature fibers, minted scopes, and persisted store state on one axis.
 

packages/client/test-runtime/README.zh.md

@@ -4,7 +4,7 @@
 
 面向 client feature 测试的 jsdom slot 测试运行时：真实 Cordis `Context`、生产 `SlotsService` 与 web-react 渲染器，围绕带类型的 session/workspace 测试替身组装。feature 套件无需逐套件手搭机器即可测遍声明、注册、scope、store、inject、渲染、更新与销毁——且不存在任何生产逻辑的第二份实现。
 
-替身实现的正是 feature 经 ctx 拿到的对外面（`TestSessions implements ISessions`、`TestWorkspaces implements IWorkspaces`；每个 fixture session 是 `FixtureSession implements SessionFace`），生产面一旦改形，测试台在编译期即断，而非静默漂移。provide bundle 材料化直接运行生产 `SessionProvideChannel`——与 `SessionsService` 共用同一份实现。fixture 灌入的是普通数据：列表行、会话快照（经 `updateSnapshot` 以 immer 补丁改写）、projection 值，以及按 `ISession` 取型的行为桩——spec 调用未打桩的动词时报错自明。带类型的 `provide()` 将已声明服务名的 fake 约束为该服务对外面的 `Partial` 子集。
+替身实现的正是 feature 经 ctx 拿到的对外面（`TestSessions implements ISessions`、`TestWorkspaces implements IWorkspaces`；每个 fixture session 是 `FixtureSession implements SessionFace`；`stubSettingsScope` 是发布由测试驱动、带写入 spy 的 `SettingsScope`），生产面一旦改形，测试台在编译期即断，而非静默漂移。provide bundle 材料化直接运行生产 `SessionProvideChannel`——与 `SessionsService` 共用同一份实现。fixture 灌入的是普通数据：列表行、会话快照（经 `updateSnapshot` 以 immer 补丁改写）、projection 值，以及按 `ISession` 取型的行为桩——spec 调用未打桩的动词时报错自明。带类型的 `provide()` 将已声明服务名的 fake 约束为该服务对外面的 `Partial` 子集。
 
 局部 DOM 快照：`declare(children)` 注册自动 frame，逐 key 的 `<div data-slot>` 包裹层即快照根；`renderSlot(key, owner)` 返回该 slot 的局部视图（container、限定范围的 Testing Library 查询、原位 `update(owner)`）；注册的快照序列化器把 CSS-module 哈希类名折回语义名（`_frame_a1b2c3` → `frame`）保持 `.snap` 只含结构，并把 `<svg>` 内部折叠为 `data-content` 指纹。需要自定义页面 frame 的套件改用 `root.declare(children, Frame)`；`mount(plugin)` 在真实 fiber 上运行并对缺失服务先行报错；`dispose()` 沿单一轴拆除视图、feature fiber、已铸 scope 与持久化 store 状态。
 

packages/client/test-runtime/src/index.ts

@@ -34,6 +34,8 @@ import type { Stabilizer } from './fixtures.ts'
 
 export { domSnapshotSerializer, registerDomSnapshotSerializer } from './snapshot.ts'
 export { FixtureSession, TestSessions } from './sessions.ts'
+export { stubSettingsScope } from './settings-scope.ts'
+export type { StubSettingsScope } from './settings-scope.ts'
 export { TestWorkspaces } from './workspaces.ts'
 export { conversationSnapshot, workspaceListState } from './fixtures.ts'
 export type { SessionBehaviorOverrides, SessionFixture, Stabilizer } from './fixtures.ts'

packages/client/test-runtime/src/settings-scope.ts

@@ -0,0 +1,48 @@
+/** Test double for the client settings-scope seam. */
+import { vi } from 'vitest'
+import type { SettingsScope, SettingsScopeSnapshot } from '@deepseek-ai/dsh-client-runtime/client'
+
+/** Handle over one stubbed scope: the scope, its write spy, and publication controls. */
+export interface StubSettingsScope<T> {
+  /** The scope face handed to the service under test. */
+  scope: SettingsScope<T>
+  /** Spy behind `scope.set`; resolves immediately. */
+  set: ReturnType<typeof vi.fn>
+  /** @returns how many listeners are currently subscribed (disposal assertions). */
+  listenerCount(): number
+  /**
+   * Replace part of the snapshot and notify subscribers, as a Host
+   * acceptance would.
+   * @param next - snapshot fields to replace.
+   */
+  publish(next: Partial<SettingsScopeSnapshot<T>>): void
+}
+
+/**
+ * Build an in-memory settings scope for service specs: starts in the host
+ * loading state, records writes, and lets the test publish Host acceptances.
+ * @returns the stub handle.
+ */
+export function stubSettingsScope<T>(): StubSettingsScope<T> {
+  let snapshot: SettingsScopeSnapshot<T> = {
+    status: 'loading', value: undefined, revision: undefined, writable: false, mode: 'host',
+  }
+  const listeners = new Set<() => void>()
+  const set = vi.fn(() => Promise.resolve())
+  return {
+    scope: {
+      getSnapshot: () => snapshot,
+      subscribe: (listener) => {
+        listeners.add(listener)
+        return () => { listeners.delete(listener) }
+      },
+      set,
+    },
+    set,
+    listenerCount: () => listeners.size,
+    publish: (next) => {
+      snapshot = { ...snapshot, ...next }
+      for (const listener of [...listeners]) listener()
+    },
+  }
+}