fix(client,host): review round — hooks-compartment occupancy, StrictMode re-arm, internal flow module, honest swap comment

- Directory-flow occupancy moves onto the inject face's reserved hooks
  compartment: apply publishes a stable observable per surface and the
  renderer binds useDirectoryFlow — no hand-rolled component subscriptions
  (the client contract's channel for registrant-private reactive facts).
- The native flow's alive guard re-arms in effect setup: StrictMode's
  development replay ran the cleanup once and every later outcome was
  discarded.
- NativeDirectoryFlow moves to a package-internal module; ./client exports
  only the Loader surface, tests import the internal module directly.
- The composition swap comment no longer advertises -browse as a complete
  swap before its dialog lands (stacked follow-up).

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

@@ -88,18 +88,18 @@ describe('ui-workspace apply', () => {
 
     const browser = (b.slots.entries('sidebar.workspaces')[0]!.inject as () => WorkspaceBrowserInjected)()
     const picker = (b.slots.entries('conversation.hero.workspace')[0]!.inject as () => WorkspacePickerInjected)()
-    expect(browser.hasDirectoryFlow()).toBe(false)
-    expect(picker.hasDirectoryFlow()).toBe(false)
-    // A flow occupant flips exactly its own surface.
+    expect(browser.hooks.directoryFlow.getSnapshot()).toBe(false)
+    expect(picker.hooks.directoryFlow.getSnapshot()).toBe(false)
+    // A flow occupant flips exactly its own surface, and the source notifies.
     const notified = vi.fn()
-    const unsubscribe = browser.subscribeDirectoryFlow(notified)
+    const unsubscribe = browser.hooks.directoryFlow.subscribe(notified)
     const dispose = b.slots.register({ name: 'sidebar.workspaces.directoryFlow' } as never, () => null)
-    expect(browser.hasDirectoryFlow()).toBe(true)
-    expect(picker.hasDirectoryFlow()).toBe(false)
+    expect(browser.hooks.directoryFlow.getSnapshot()).toBe(true)
+    expect(picker.hooks.directoryFlow.getSnapshot()).toBe(false)
     await Promise.resolve()
     expect(notified).toHaveBeenCalled()
     dispose()
-    expect(browser.hasDirectoryFlow()).toBe(false)
+    expect(browser.hooks.directoryFlow.getSnapshot()).toBe(false)
     unsubscribe()
   })
 

packages/client/ui-workspace/tests/workspace-browser.spec.tsx

@@ -59,8 +59,7 @@ function mount(overrides: Partial<WorkspaceBrowserProps> = {}) {
     deleteWorkspace: vi.fn(async () => {}),
     insertSessionBefore: vi.fn(async () => {}),
     createWorkspace: vi.fn(async () => workspace('created', [])),
-    hasDirectoryFlow: () => true,
-    subscribeDirectoryFlow: () => () => {},
+    useDirectoryFlow: bindSnapshotSelector({ getSnapshot: () => true, subscribe: () => () => {} }),
     renderSlot: ((_name: string, owner: { open: boolean }) => (owner.open ? <div data-testid="directory-flow" /> : null)) as never,
     ...overrides,
   }

packages/client/ui-workspace/tests/workspace-picker.spec.tsx

@@ -6,6 +6,7 @@ import type {
 } from '@deepseek-ai/dsh-client-runtime/client'
 import { WorkspaceCreateError } from '@deepseek-ai/dsh-client-runtime/client'
 import type { DirectoryFlowOwnerProps } from '../src/client/contract/slots.ts'
+import { bindSnapshotSelector } from '@deepseek-ai/dsh-client-web-react'
 import { WorkspacePicker } from '../src/client/WorkspacePicker.tsx'
 
 afterEach(cleanup)
@@ -50,16 +51,19 @@ function flowProbe() {
   return { probe, renderSlot }
 }
 
-/** Manual occupancy source: flip() drives the uSES subscription like a real registration change. */
+/** Manual occupancy source bound like the renderer would: flip() drives the hook like a real registration change. */
 function occupancySource(initial = true) {
   let occupied = initial
   const listeners = new Set<() => void>()
-  return {
-    hasDirectoryFlow: () => occupied,
-    subscribeDirectoryFlow: (listener: () => void) => {
+  const useDirectoryFlow = bindSnapshotSelector({
+    getSnapshot: () => occupied,
+    subscribe: (listener: () => void) => {
       listeners.add(listener)
       return () => { listeners.delete(listener) }
     },
+  })
+  return {
+    useDirectoryFlow,
     flip: (next: boolean) => {
       occupied = next
       for (const listener of [...listeners]) listener()
@@ -85,8 +89,7 @@ function mount(
       onPick={onPick}
       onClose={onClose}
       createWorkspace={createWorkspace}
-      hasDirectoryFlow={occupancy.hasDirectoryFlow}
-      subscribeDirectoryFlow={occupancy.subscribeDirectoryFlow}
+      useDirectoryFlow={occupancy.useDirectoryFlow}
       renderSlot={renderSlot}
     />
   )
@@ -265,7 +268,7 @@ describe('WorkspacePicker', () => {
       <WorkspacePicker
         open useSessions={hook(sessions)} useWorkspaces={hook(workspaceState([]))}
         onPick={vi.fn()} onClose={vi.fn()} createWorkspace={vi.fn()}
-        hasDirectoryFlow={() => true} subscribeDirectoryFlow={() => () => {}} renderSlot={renderSlot}
+        useDirectoryFlow={occupancySource().useDirectoryFlow} renderSlot={renderSlot}
       />,
     )
     expect(screen.queryByRole('menu')).toBeNull()
@@ -280,7 +283,7 @@ describe('WorkspacePicker', () => {
       <WorkspacePicker
         open anchorRef={anchor()} useSessions={hook(sessions)} useWorkspaces={hook(state)}
         onPick={vi.fn()} onClose={vi.fn()} createWorkspace={vi.fn()}
-        hasDirectoryFlow={() => true} subscribeDirectoryFlow={() => () => {}} renderSlot={renderSlot}
+        useDirectoryFlow={occupancySource().useDirectoryFlow} renderSlot={renderSlot}
       />,
     )
     expect(screen.getByRole('status').textContent).toBe('Loading workspaces…')