test: pin document.hasFocus in status timer test (useViewedInterval gating)

apps/desktop/src/components/assistant-ui/thread/status.test.tsx

@@ -19,6 +19,10 @@ describe('ResponseLoadingIndicator timer', () => {
   beforeEach(() => {
     vi.useFakeTimers()
     vi.setSystemTime(new Date('2026-01-01T00:00:00.000Z'))
+    // useViewedInterval gates ticking on document focus + visibility; jsdom's
+    // hasFocus() is unreliable across runners, so pin it (same as the
+    // background-sync backstop tests).
+    vi.spyOn(document, 'hasFocus').mockReturnValue(true)
     __resetElapsedTimerRegistryForTests()
   })
 
@@ -27,6 +31,7 @@ describe('ResponseLoadingIndicator timer', () => {
     $activeSessionId.set(null)
     $turnStartedAt.set(null)
     __resetElapsedTimerRegistryForTests()
+    vi.restoreAllMocks()
     vi.useRealTimers()
   })