feat(studio): Doctor + Modules localized + sparse-store federation nudge (v0.25.0)

Two threads.

Translation expansion: every visible string on the Doctor
page (section headers, status text, button labels, daemon-
control card, daemon-files panel, update banner) and the
Modules page (recent-activity strip, capabilities label,
uninstall dialog + toast) flips between DE and EN with the
sidebar toggle. Adds ~50 ARB keys split between
`app_en.arb` / `app_de.arb`. Pluralised + parametrised
strings (`{n} events verified`, `Running on {name}: {endpoint}`)
use the standard ICU placeholder syntax so future locales
slot in without code changes.

Sparse-store federation nudge: the Store page renders an
inline banner above the grid when the operator has zero
federated entries — single biggest store-fullness lever is
configuring an MCP server / n8n endpoint, so the banner
says exactly that and the button opens Settings straight
to the editor. Banner dismisses automatically the next
render after a federated entry appears.

Coverage stand for translation: Doctor + Modules + sidebar
+ page titles + nav + Cmd+K labels are bilingual. Settings
dialog, Approvals cards, Audit drilldown, MCP/n8n editors,
Store search hint + filter chips remain English-literal.
The infrastructure (ARB plumbing, generator hookup,
locale-notifier) means each follow-up surface is a
one-line ARB edit + one call-site swap.

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

lib/main.dart

@@ -26,7 +26,7 @@ import 'widgets/widgets.dart';
 /// Studio's own build version. Bump on every UI commit so the
 /// running app self-identifies — visible in the sidebar header
 /// and quick-glance proof that you're seeing the current build.
-const String kStudioVersion = '0.24.0';
+const String kStudioVersion = '0.25.0';
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();