fix(mobile): let an unmounted quick-command row emit nothing on a refusal

The haptic I added ran before the mounted guard, so a copy pressed on a row that
then scrolled out of the list, or a sheet closed over it, still buzzed when the
rejection arrived. A buzz with no row to explain it is feedback for nothing, and
the guard was already there for the feedback state one line below.

Red-first: press, unmount, then reject. The success path already guarded first.

Claude-Session: https://claude.ai/code/session_01JNnE9qzUZMMnqpZWCqM3nb

mobile/src/session/QuickCommandRow.test.ts

@@ -87,18 +87,20 @@ describe('the quick-command row when the pasteboard refuses the text', () => {
     return button
   }
 
+  function rowProps() {
+    return {
+      command: COMMAND,
+      first: true,
+      onLaunch: vi.fn(),
+      onEdit: vi.fn(),
+      onDelete: vi.fn(),
+      disabled: false
+    }
+  }
+
   async function mountAndCopy(): Promise<void> {
     await act(async () => {
-      renderer = create(
-        createElement(QuickCommandRow, {
-          command: COMMAND,
-          first: true,
-          onLaunch: vi.fn(),
-          onEdit: vi.fn(),
-          onDelete: vi.fn(),
-          disabled: false
-        })
-      )
+      renderer = create(createElement(QuickCommandRow, rowProps()))
     })
     await act(async () => {
       copyButton().props.onPress()
@@ -112,6 +114,30 @@ describe('the quick-command row when the pasteboard refuses the text', () => {
     expect(haptics.notificationAsync).toHaveBeenCalledWith('error')
   })
 
+  it('emits nothing at all when the row is gone before the refusal arrives', async () => {
+    // A copy pressed on a row that then scrolls out of the list, or a sheet closed over it. The
+    // rejection still arrives, and a buzz with no row to explain it is feedback for nothing.
+    let refuse: ((error: Error) => void) | undefined
+    clipboard.setStringAsync.mockImplementation(
+      () =>
+        new Promise((_resolve, reject) => {
+          refuse = reject
+        })
+    )
+    await act(async () => {
+      renderer = create(createElement(QuickCommandRow, rowProps()))
+    })
+    await act(async () => {
+      copyButton().props.onPress()
+    })
+    act(() => renderer?.unmount())
+    renderer = null
+    await act(async () => {
+      refuse?.(new Error('pasteboard refused'))
+    })
+    expect(haptics.notificationAsync).not.toHaveBeenCalled()
+  })
+
   it('shows the copied label and no error buzz when the write lands', async () => {
     // The control: a failure assertion is only evidence if the success path reads differently.
     clipboard.setStringAsync.mockResolvedValue(true)

mobile/src/session/QuickCommandRow.tsx

@@ -75,12 +75,14 @@ export function QuickCommandRow({
       }
       setFeedback({ body, status: 'copied' })
     } catch {
-      // The row says so on its own control rather than in a toast; the buzz is the part a thumb
-      // resting on the button it just pressed can notice without looking.
-      triggerError()
+      // The guard first: a row unmounted before the refusal arrives has nothing to explain a buzz
+      // with, and the feedback it would set is read by a component that is gone.
       if (!mountedRef.current) {
         return
       }
+      // The row says so on its own control rather than in a toast; the buzz is the part a thumb
+      // resting on the button it just pressed can notice without looking.
+      triggerError()
       setFeedback({ body, status: 'failed' })
     }
     if (copyResetTimerRef.current) {