Replaces 6 setTimeout sleeps with vi.waitFor and expect.element
auto-wait, and converts 9 .not.toThrow smoke tests into assertions
on the rendered PDF nav controls (Zurück/Weiter/Vergrößern/Verkleinern)
and the conditional outdated-annotation notice / annotation visibility
toggle. transcribeMode test now mocks the annotations fetch so the
toggle button is actually rendered (annotationCount > 0 guard).
Runtime: 33s → 4.5s.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Empty state when url is empty (no controls, placeholder shown),
loaded state with controls, annotationsDimmed branch, transcribeMode
flag, documentFileHash filtering branch.
6 tests covering ~10 branches.
Refs #496.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>