feat(studio): Flows + Module sheet + System-AI editor i18n (v0.28.0)

- Localize Flows page: app-bar title and reload tooltip,
  hub-unreachable / no-saved-flows empty states, run-flow input
  dialog (title with flow name, description, hint, Cancel /
  Run), running dialog (title, "Flow running…" status, no-output
  message, Close button), flow-card Run button.
- Localize the module-sheet bottom sheet: failed-to-load text,
  Capabilities and "Declared permissions" section headers,
  no-permissions placeholder copy.
- Localize the System-AI configuration dialog: title, intro
  paragraph, provider dropdown label, endpoint label, API-key
  env-var label (required vs optional) and disclaimer, privacy
  mode header and three options (Off / Redacted / Full) plus
  their descriptions, test-result panel ("Connection ok" /
  "Connection failed", "Reply: …" prefix), model picker (label,
  hint fallback, helper text with Ollama variant, Refresh /
  Pull / Pulling… buttons, list errors and empty states),
  hardware banner ("Detected: …" + " · curation reviewed …"
  suffix), suitability legend (recommended / balanced / small /
  large / huge / unknown), cache row with pluralized count and
  Clear button, cache cleared / clear-failed toasts, pull-empty
  / pull-failed errors. Suitability label moved off a getter
  onto a `labelFor(BuildContext)` method so it can read the
  current locale.

Provider preset descriptions and modelHint strings stay in
English in `_ProviderPreset.all` — they're tightly coupled to
the wire-protocol identifiers and would require a runtime
factory rebuild rather than a const list.

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 = '0.27.0';
+const String kStudioVersion = '0.28.0';
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();