feat(localization): Implement Swedish localization and error messages

- Added localization support for Swedish and English languages.
- Integrated localized strings for user messages in the API error mapper.
- Updated UI components to use localized strings for labels and messages.
- Ensured all error messages are context-aware and utilize the localization framework.
- Created regression test to prevent common ASCII fallbacks in Swedish UI text.

flutter/lib/features/recipes/presentation/recipe_detail_screen.dart

@@ -36,7 +36,7 @@ class RecipeDetailScreen extends ConsumerWidget {
       body: recipeAsync.when(
         loading: () => const LoadingStateView(label: 'Laddar recept...'),
         error: (error, _) => ErrorStateView(
-          message: mapErrorToUserMessage(error),
+          message: mapErrorToUserMessage(error, context),
           onRetry: () => ref.invalidate(recipeDetailProvider(recipeId)),
         ),
         data: (recipe) => _RecipeBody(recipe: recipe),
@@ -92,7 +92,7 @@ class _DeleteButton extends ConsumerWidget {
     } on ApiException catch (e) {
       if (!context.mounted) return;
       ScaffoldMessenger.of(context).showSnackBar(
-        SnackBar(content: Text(mapErrorToUserMessage(e))),
+        SnackBar(content: Text(mapErrorToUserMessage(e, context))),
       );
     }
   }