feat(studio): localise Settings sidebar + add inline help docs + Approvals doc

Three operator-UX gaps closed:

  - Settings dialog's six-category sidebar (General / Appearance /
    System AI / Integrations / Security / Maintenance) was
    hardcoded English; now flows through AppLocalizations
    ("Allgemein" / "Darstellung" / "System-KI" / "Integrationen" /
    "Sicherheit" / "Wartung"). Same for the per-panel title +
    description.
  - Per-channel daemon-action labels ('enable autostart' /
    'disable autostart' / 'daemon restart' etc.) and the
    OK / Failed result line in the toast also moved to l10n,
    so the system-action feedback reads as one language.
  - New 'Approvals' doc bundle (en + de) under assets/docs/,
    registered as a fifth doc card on Welcome plus exposed via
    the new public  helper. The
    Approvals, Audit and Doctor app-bars grow a Help icon button
    next to Refresh that opens the matching doc in the existing
    bottom-sheet reader — no extra screen, no learning curve.

Studio bumped to 0.67.0; editor path-override pulls in 0.20.1
(flow-list row polish).

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/pages/approvals.dart

@@ -8,6 +8,7 @@ import '../l10n/app_localizations.dart';
 import '../theme/theme.dart';
 import '../theme/tokens.dart';
 import '../widgets/widgets.dart';
+import 'welcome.dart' show showFaiDoc;
 
 class ApprovalsPage extends StatefulWidget {
   const ApprovalsPage({super.key});
@@ -213,6 +214,11 @@ class _ApprovalsPageState extends State<ApprovalsPage>
           ],
         ),
         actions: [
+          IconButton(
+            icon: const Icon(Icons.help_outline, size: 18),
+            tooltip: AppLocalizations.of(context)!.helpTooltip,
+            onPressed: () => showFaiDoc(context, 'approvals'),
+          ),
           IconButton(
             icon: const Icon(Icons.refresh, size: 18),
             tooltip: AppLocalizations.of(context)!.approvalsReloadTooltip,