fix(host,client): abort superseded listings on the wire; keep the native swap resolvable

Supersession (newer navigation, path editing, closing, unmount) now
aborts the in-flight listing's request instead of only discarding its
result: the browser mints an AbortController per listing, the signal
rides the workspace face (IWorkspaces.listDirectory gains an optional
signal) onto the fetch carrier, and the Host scan stops with it (817's
cancellation chain). apps/cli keeps both picker packages as dependencies
so the documented one-row cordis.yml swap to the native backend resolves
at boot.

packages/host/directory-picker-browse/tests/directory-browser.spec.tsx

@@ -95,7 +95,7 @@ describe('DirectoryBrowser', () => {
   it('opens at the Host home as one wide column, hides hidden entries, and roots the crumbs at Home', async () => {
     const b = mount()
     await waitFor(() => { expect(screen.getByRole('listitem')).toBeTruthy() })
-    expect(b.listDirectory).toHaveBeenCalledWith(undefined)
+    expect(b.listDirectory).toHaveBeenCalledWith(undefined, expect.any(AbortSignal))
     expect(columns()).toHaveLength(1)
     expect(screen.getByRole('listitem').textContent).toBe('Documents')
     expect(screen.queryByText('.config')).toBeNull()
@@ -113,7 +113,7 @@ describe('DirectoryBrowser', () => {
     expect(selectedRow.textContent).toBe('Documents')
     expect(rowButton(selectedRow).getAttribute('aria-current')).toBe('true')
     expect(within(preview!).getByRole('listitem').textContent).toBe('harness')
-    expect(b.listDirectory).toHaveBeenLastCalledWith(DOCS)
+    expect(b.listDirectory).toHaveBeenLastCalledWith(DOCS, expect.any(AbortSignal))
     expect(within(screen.getByRole('navigation')).getByRole('button', { name: 'Documents' })).toBeTruthy()
   })
 
@@ -130,6 +130,29 @@ describe('DirectoryBrowser', () => {
     expect(rowButton(selectedRow).getAttribute('aria-current')).toBe('true')
   })
 
+  it('aborts a superseded listing on the wire, and the in-flight one on close', async () => {
+    const signals: (AbortSignal | undefined)[] = []
+    const gates: (() => void)[] = []
+    const listDirectory = vi.fn((path?: string, signal?: AbortSignal) => {
+      signals.push(signal)
+      if (signals.length === 1) return Promise.resolve(listingFor(path))
+      // Later listings hang until released: supersession must abort them
+      // on the wire, not merely discard their eventual results.
+      return new Promise<DirectoryListing>((resolve) => { gates.push(() => { resolve(listingFor(path)) }) })
+    })
+    const b = mount({ listDirectory })
+    await waitFor(() => { expect(screen.getByRole('listitem')).toBeTruthy() })
+    fireEvent.click(rowButton(screen.getByRole('listitem')))
+    expect(signals).toHaveLength(2)
+    // A crumb jump supersedes the hanging preview: its request aborts.
+    fireEvent.click(screen.getByRole('button', { name: 'browser.home' }))
+    expect(signals[1]?.aborted).toBe(true)
+    expect(signals[2]?.aborted).toBe(false)
+    // Closing the dialog aborts the still-pending navigation too.
+    b.view.rerender(<DirectoryBrowser {...b.props} listDirectory={listDirectory} open={false} />)
+    expect(signals[2]?.aborted).toBe(true)
+  })
+
   it('jumps back through a crumb into a fresh single-column level', async () => {
     mount()
     await waitFor(() => { expect(screen.getByRole('listitem')).toBeTruthy() })
@@ -195,7 +218,7 @@ describe('DirectoryBrowser', () => {
     // rows nor status behind.
     await waitFor(() => { expect(screen.getByRole('listitem').textContent).toBe('Documents') })
     expect(listDirectory).toHaveBeenCalledTimes(2)
-    expect(listDirectory).toHaveBeenLastCalledWith(undefined)
+    expect(listDirectory).toHaveBeenLastCalledWith(undefined, expect.any(AbortSignal))
   })
 
   it('passes the entered path to the Host untrimmed (trim only gates blank drafts)', async () => {
@@ -207,7 +230,7 @@ describe('DirectoryBrowser', () => {
     fireEvent.change(input, { target: { value: `${DOCS} ` } })
     fireEvent.keyDown(input, { key: 'Enter' })
     // A trailing space may name a real directory; trimming would list its sibling.
-    await waitFor(() => { expect(listDirectory).toHaveBeenLastCalledWith(`${DOCS} `) })
+    await waitFor(() => { expect(listDirectory).toHaveBeenLastCalledWith(`${DOCS} `, expect.any(AbortSignal)) })
   })
 
   it('surfaces an unreadable target as an alert and keeps the edit open for correction', async () => {
@@ -347,7 +370,7 @@ describe('DirectoryBrowser', () => {
     expect(b.listDirectory.mock.calls.length).toBe(listCalls)
     fireEvent.compositionEnd(pathInput)
     fireEvent.keyDown(pathInput, { key: 'Enter' })
-    await waitFor(() => { expect(b.listDirectory).toHaveBeenLastCalledWith(DOCS) })
+    await waitFor(() => { expect(b.listDirectory).toHaveBeenLastCalledWith(DOCS, expect.any(AbortSignal)) })
     // Create dialog: same guard.
     fireEvent.click(screen.getByRole('button', { name: 'browser.newFolder' }))
     const nameInput = screen.getByLabelText('browser.folderName')
@@ -764,6 +787,6 @@ describe('DirectoryBrowser', () => {
     b.view.rerender(<DirectoryBrowser {...b.props} open />)
     await waitFor(() => { expect(screen.getByRole('listitem').textContent).toBe('Documents') })
     expect(columns()).toHaveLength(1)
-    expect(b.listDirectory).toHaveBeenLastCalledWith(undefined)
+    expect(b.listDirectory).toHaveBeenLastCalledWith(undefined, expect.any(AbortSignal))
   })
 })