fix tests for sidebar/settings refactor + weather archive fallback

- DayPlanSidebar: add aria-label to undo button, replace title with aria-label
  so tests can still locate buttons by accessible name after tooltip refactor
- tests: switch getByTitle("Add Note") to getByLabelText
- tests: find undo button via aria-label (new expand/collapse button also uses
  width:30, breaking the old style-based lookup)
- PlacesSidebar tests: loosen "All" button regex to account for count badge
- DisplaySettingsTab tests: use getByRole for Auto button (two "Auto" spans
  coexist for mobile/desktop); handle multiple English matches in lang test
- weatherService tests: past-date case now expects an archive fetch instead
  of an immediate no_forecast error

client/src/components/Planner/DayPlanSidebar.tsx

@@ -1074,6 +1074,7 @@ const DayPlanSidebar = React.memo(function DayPlanSidebar({
               <button
                 onClick={onUndo}
                 disabled={!canUndo}
+                aria-label={t('undo.button')}
                 onMouseEnter={() => setUndoHover(true)}
                 onMouseLeave={() => setUndoHover(false)}
                 style={{