fix: resolve auth:expired race condition and force SW cache refresh

- Add _pendingLoginRedirect flag in router.js to handle auth:expired
  events that fire during active navigation (isNavigating=true).
  Previously the navigate('/login') call was silently dropped, leaving
  the user stuck on the dashboard with an error toast.
- Bump SHELL_CACHE v33→v34 and PAGES_CACHE v28→v29 to force cache
  invalidation on iOS devices still running the pre-CSRF-fix code.
- Add err.status to dashboard error log for easier diagnostics.

public/pages/dashboard.js

@@ -655,7 +655,7 @@ export async function render(container, { user }) {
     weather      = weatherRes.data ?? null;
     widgetConfig = prefsRes.data?.dashboard_widgets ?? DEFAULT_WIDGET_CONFIG;
   } catch (err) {
-    console.error('[Dashboard] Ladefehler:', err.message);
+    console.error('[Dashboard] Ladefehler:', err.message, 'Status:', err.status ?? 'network');
     window.oikos?.showToast(t('dashboard.loadError'), 'warning');
   }