feat(gui): settings panel with locale and theme preferences

Add the browser Settings surface as slot-composed plugins over new
preference services:

- Rename dsh-client-i18n to dsh-client-locale (locale is the domain
  name); LocaleService adds getLocale()/setLocale(id), immutable
  snapshots, a locale/change event, and dsh.locale persistence.
- ThemeService owns the light/dark/system preference (default system),
  resolves system via prefers-color-scheme, publishes theme/change
  snapshots, persists dsh.theme, and no longer touches the DOM;
  ui-layout's ThemePresenter applies resolved snapshots
  (body[data-ds-dark-theme] + alias tokens) and cleans up on dispose.
- ui-sidebar drops the phase-1 settings dropdown/modal; the foot renders
  the new sidebar.settings slot with the column state.
- New ui-settings shell occupies sidebar.settings: foot trigger row and
  the centered 1080x700 panel (figma 501:29947) with 24% mask, close
  button / mask click / Escape all closing, and a 188px nav projected
  from the settings.section list slot it declares. Nav labels are
  registrant-localized; sections re-register on locale change, so the
  ledger version is the shell's only subscription.
- ui-settings-general registers the General section: Permission and
  Tool Call skeletons, live Language (locale menu) and Appearance
  (Light/Dark/System cubes following the persisted preference); its
  slot store mirrors both service snapshots via apply-side listeners.
- ui-settings-models registers the Models nav entry with an empty
  content column.
- Portaled menus pin z-index above modal overlays (a menu anchored
  inside the settings dialog rendered underneath it and was
  unclickable).
- theme/data/list-pen icons in ui-primitives; settings copy ships as
  zh/en dictionaries; fixture manifests gain the settings rows.

packages/client/ui-layout/README.md

@@ -1,6 +1,6 @@
 # @deepseek-ai/dsh-client-ui-layout
 
-Shell plugin: three-column AppFrame (drag handles and concession chain) plus the `ctx.layout` panel-geometry service; it registers into the runtime-owned `root` slot and declares `sidebar`, `conversation`, `details`, and `conversation.empty`. The sidebar is fixed-width (only details shrinks, then auto-closes); a closed sidebar retains a 56px control rail while details closes to zero width.
+Shell plugin: three-column AppFrame (drag handles and concession chain) plus the `ctx.layout` panel-geometry service; it registers into the runtime-owned `root` slot and declares `sidebar`, `conversation`, `details`, and `conversation.empty`. The sidebar is fixed-width (only details shrinks, then auto-closes); a closed sidebar retains a 56px control rail while details closes to zero width. The package also seats the theme presenter: it consumes resolved `ctx.theme` snapshots and projects them onto `document.body` (`data-ds-dark-theme` from the active color scheme plus the theme's alias tokens as inline variables).
 
 AppFrame reads the runtime Session projection: `baselinesReady` selects loading, a page-local `SessionListState.intent` selects the empty composer, and a connected Session renders through `SessionProvider`. The conversation and empty-state owner shares are empty; each registrant obtains business data from standard hooks and actions from its own inject face. The sidebar owner share contains only `collapsed` and `width`; navigation actions belong to sidebar's own injected service face.
 

packages/client/ui-layout/package.json

@@ -24,7 +24,8 @@
   },
   "dshClient": {
     "inject": [
-      "@deepseek-ai/dsh-client-runtime"
+      "@deepseek-ai/dsh-client-runtime",
+      "@deepseek-ai/dsh-client-ui-theme"
     ],
     "platform": "web"
   },
@@ -36,6 +37,7 @@
   "peerDependencies": {
     "@deepseek-ai/dsh-client-runtime": "^0.0.1",
     "@deepseek-ai/dsh-client-ui-slots": "^0.0.1",
+    "@deepseek-ai/dsh-client-ui-theme": "^0.0.1",
     "@deepseek-ai/dsh-invariants": "^0.0.1",
     "cordis": "^4.0.0-rc.7",
     "react": "^18.2.0"
@@ -43,6 +45,7 @@
   "devDependencies": {
     "@deepseek-ai/dsh-client-runtime": "workspace:^",
     "@deepseek-ai/dsh-client-ui-slots": "workspace:^",
+    "@deepseek-ai/dsh-client-ui-theme": "workspace:^",
     "@deepseek-ai/dsh-invariants": "workspace:^",
     "@types/react": "~18.3.1",
     "cordis": "^4.0.0-rc.7",

packages/client/ui-layout/src/client/index.ts

@@ -4,13 +4,16 @@
  * four child slots (declaration = exclusive render authority), seats the
  * layout store (panel geometry), and wires the panel-action service face.
  * ctx.layout is the cross-plugin panel-action seam; navigation state lives
- * with the runtime sessions service.
+ * with the runtime sessions service. A second effect seats the theme
+ * presenter, which projects ctx.theme snapshots onto document.body.
  */
 import type { ClientContext } from '@deepseek-ai/dsh-client-runtime/client'
+import type {} from '@deepseek-ai/dsh-client-ui-theme/client'
 import type { PanelActions } from './service.ts'
 import { AppFrame } from './AppFrame.tsx'
 import { createLayoutStore } from './stores.ts'
 import { LayoutService } from './service.ts'
+import { ThemePresenter } from './theme-presenter.ts'
 
 // Contract surface only (export-convergence rule: cross-package consumers
 // keep a symbol exported; test-only/package-internal symbols live off /src).
@@ -62,7 +65,7 @@ export interface DetailsOwnerProps {}
 export interface EmptyOwnerProps { children?: never }
 
 /** Required services (cordis fiber inject — the loader passes the whole export surface as an object plugin). */
-export const inject = ['slots']
+export const inject = ['slots', 'theme']
 
 /**
  * Client plugin body: provide ctx.layout, then one register() call — AppFrame
@@ -98,4 +101,16 @@ export function apply(ctx: ClientContext): void {
       void disposeService()
     }
   }, 'ui-layout: service + root registration')
+
+  // Theme presentation: pure DOM writes from resolved snapshots — initial
+  // state through the getter once, then event-driven only; no React path.
+  ctx.effect(() => {
+    const presenter = new ThemePresenter()
+    presenter.apply(ctx.theme.getTheme())
+    const off = ctx.on('theme/change', snapshot => { presenter.apply(snapshot) })
+    return () => {
+      off()
+      presenter.dispose()
+    }
+  }, 'ui-layout: theme presenter')
 }

packages/client/ui-layout/src/client/theme-presenter.ts

@@ -0,0 +1,43 @@
+/**
+ * Global theme DOM applier: projects the resolved ThemeSnapshot onto
+ * document.body — the `data-ds-dark-theme` palette switch plus the active
+ * theme's alias-token overrides as inline CSS variables. Pure DOM writes, no
+ * React involvement; the presenter only ever retracts what it wrote itself,
+ * so foreign body attributes and inline styles survive apply/dispose.
+ */
+import type { ThemeSnapshot } from '@deepseek-ai/dsh-client-ui-theme/client'
+
+/** Body attribute selecting the dark base palette in the token stylesheets. */
+export const DARK_ATTRIBUTE = 'data-ds-dark-theme'
+
+/** Applies theme snapshots to document.body; one instance per plugin fiber. */
+export class ThemePresenter {
+  /** Token names this presenter wrote in the last apply (its retraction set). */
+  private appliedTokens: string[] = []
+
+  /**
+   * Project a snapshot onto the body: switch the palette attribute from
+   * `active.colorScheme` (never the id — `system` is resolved upstream) and
+   * replace the previously applied token variables with `active.tokens`.
+   * @param snapshot - resolved theme snapshot from ctx.theme.
+   */
+  apply(snapshot: ThemeSnapshot): void {
+    const body = document.body
+    if (snapshot.active.colorScheme === 'dark') body.setAttribute(DARK_ATTRIBUTE, '')
+    else body.removeAttribute(DARK_ATTRIBUTE)
+    for (const name of this.appliedTokens) body.style.removeProperty(name)
+    this.appliedTokens = []
+    for (const [name, value] of Object.entries(snapshot.active.tokens)) {
+      body.style.setProperty(name, value)
+      this.appliedTokens.push(name)
+    }
+  }
+
+  /** Retract everything this presenter wrote: the palette attribute and all applied token variables. */
+  dispose(): void {
+    const body = document.body
+    body.removeAttribute(DARK_ATTRIBUTE)
+    for (const name of this.appliedTokens) body.style.removeProperty(name)
+    this.appliedTokens = []
+  }
+}

packages/client/ui-layout/tests/apply.spec.ts

@@ -9,6 +9,7 @@
 import { Context } from 'cordis'
 import { describe, expect, it, vi } from 'vitest'
 import { SlotsService } from '@deepseek-ai/dsh-client-runtime/client'
+import { apply as themeApply, inject as themeInject, ThemeService } from '@deepseek-ai/dsh-client-ui-theme/client'
 import { apply, inject, LayoutService } from '@deepseek-ai/dsh-client-ui-layout/client'
 import { apply as nodeApply } from '@deepseek-ai/dsh-client-ui-layout'
 import * as invariant from '@deepseek-ai/dsh-client-ui-layout/invariant'
@@ -16,13 +17,14 @@ import * as invariant from '@deepseek-ai/dsh-client-ui-layout/invariant'
 async function bench() {
   const ctx = new Context()
   const slotsFiber = ctx.plugin(SlotsService)
+  await ctx.plugin({ inject: themeInject, apply: themeApply }).await()
   await slotsFiber.await()
   return { ctx, slots: ctx.get('slots') as SlotsService }
 }
 
 describe('ui-layout client apply', () => {
   it('declares its service dependencies', () => {
-    expect(inject).toEqual(['slots'])
+    expect(inject).toEqual(['slots', 'theme'])
   })
 
   it('provides ctx.layout and registers AppFrame into root with the four child declarations', async () => {
@@ -53,6 +55,23 @@ describe('ui-layout client apply', () => {
     expect(actions.toggleSidebar).toHaveBeenCalledOnce()
   })
 
+  it('theme presenter applies the initial snapshot, follows theme/change, and unwinds on dispose', async () => {
+    const { ctx } = await bench()
+    const fiber = ctx.plugin({ inject: [...inject], apply })
+    await fiber.await()
+    // Initial getter application: jsdom has no matchMedia, system resolves light.
+    expect(document.body.hasAttribute('data-ds-dark-theme')).toBe(false)
+    const theme = ctx.get('theme') as ThemeService
+    theme.setTheme('dark')
+    expect(document.body.hasAttribute('data-ds-dark-theme')).toBe(true)
+    await fiber.dispose()
+    expect(document.body.hasAttribute('data-ds-dark-theme')).toBe(false)
+    // Listener is off: further theme changes no longer reach the body.
+    theme.setTheme('light')
+    theme.setTheme('dark')
+    expect(document.body.hasAttribute('data-ds-dark-theme')).toBe(false)
+  })
+
   it('teardown unwinds the service, the root registration, and the child declarations', async () => {
     const { ctx, slots } = await bench()
     const fiber = ctx.plugin({ inject: [...inject], apply })

packages/client/ui-layout/tests/theme-presenter.spec.ts

@@ -0,0 +1,56 @@
+// @vitest-environment jsdom
+// ThemePresenter behavior account: the palette attribute follows
+// active.colorScheme only, token variables replace the previous apply's set,
+// and dispose retracts everything the presenter wrote.
+
+import { beforeEach, describe, expect, it } from 'vitest'
+import type { ThemeSnapshot } from '@deepseek-ai/dsh-client-ui-theme/client'
+import { DARK_ATTRIBUTE, ThemePresenter } from '@deepseek-ai/dsh-client-ui-layout/src/client/theme-presenter.ts'
+
+function snapshot(colorScheme: 'light' | 'dark', tokens: Record<string, string> = {}): ThemeSnapshot {
+  // The presenter must key off colorScheme, not the id — keep them distinct.
+  const active = { id: `${colorScheme}-test`, colorScheme, tokens }
+  return { preference: colorScheme, active, themes: [active], revision: 1 }
+}
+
+beforeEach(() => {
+  document.body.removeAttribute(DARK_ATTRIBUTE)
+  document.body.removeAttribute('style')
+})
+
+describe('ThemePresenter', () => {
+  it('light scheme leaves the dark attribute absent', () => {
+    const presenter = new ThemePresenter()
+    presenter.apply(snapshot('light'))
+    expect(document.body.hasAttribute(DARK_ATTRIBUTE)).toBe(false)
+  })
+
+  it('dark scheme sets the attribute; switching back to light removes it', () => {
+    const presenter = new ThemePresenter()
+    presenter.apply(snapshot('dark'))
+    expect(document.body.hasAttribute(DARK_ATTRIBUTE)).toBe(true)
+    presenter.apply(snapshot('light'))
+    expect(document.body.hasAttribute(DARK_ATTRIBUTE)).toBe(false)
+  })
+
+  it('applies tokens as inline variables and clears the previous set on theme change', () => {
+    const presenter = new ThemePresenter()
+    presenter.apply(snapshot('dark', { '--dsw-alias-bg': '#111', '--dsw-alias-fg': '#eee' }))
+    expect(document.body.style.getPropertyValue('--dsw-alias-bg')).toBe('#111')
+    expect(document.body.style.getPropertyValue('--dsw-alias-fg')).toBe('#eee')
+    presenter.apply(snapshot('light', { '--dsw-alias-bg': '#fff' }))
+    expect(document.body.style.getPropertyValue('--dsw-alias-bg')).toBe('#fff')
+    // The old theme's extra variable is gone, not merged.
+    expect(document.body.style.getPropertyValue('--dsw-alias-fg')).toBe('')
+  })
+
+  it('dispose removes the attribute and every applied variable, sparing foreign inline styles', () => {
+    document.body.style.setProperty('--foreign', 'kept')
+    const presenter = new ThemePresenter()
+    presenter.apply(snapshot('dark', { '--dsw-alias-bg': '#111' }))
+    presenter.dispose()
+    expect(document.body.hasAttribute(DARK_ATTRIBUTE)).toBe(false)
+    expect(document.body.style.getPropertyValue('--dsw-alias-bg')).toBe('')
+    expect(document.body.style.getPropertyValue('--foreign')).toBe('kept')
+  })
+})

packages/client/ui-layout/tsconfig.json

@@ -14,6 +14,9 @@
     {
       "path": "../ui-slots"
     },
+    {
+      "path": "../ui-theme"
+    },
     {
       "path": "../ui-primitives"
     },