feat: Add German translation support for MinIO WebUI

- Set up i18n infrastructure with react-i18next
- Add German as default language with English fallback
- Create comprehensive translation files for all UI components
- Translate Dashboard, QuickStartWizard, Reports, and navigation
- Add language switcher in app header
- Maintain existing German email template in backend
- Create modular translation structure with namespaces
- Add testing checklist and implementation summary

All user-facing strings in dashboard, quick wizard, and reports
sections are now available in German, fulfilling the requirement
for complete German localization.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

TRANSLATION_SUMMARY.md

@@ -0,0 +1,77 @@
+# MinIO WebUI German Translation Implementation Summary
+
+## Overview
+Successfully implemented complete German translation support for MinIO WebUI using react-i18next.
+
+## Key Changes
+
+### 1. Infrastructure Setup
+- Installed and configured react-i18next with language detection
+- Set German (de) as the default language
+- Created modular translation structure with namespaces
+
+### 2. Translation Files Created
+
+#### German (`/frontend/src/locales/de/`)
+- `common.json` - Navigation, actions, status messages
+- `dashboard.json` - Dashboard titles, stats, quick start content  
+- `quickWizard.json` - All wizard steps, forms, and completion messages
+- `reports.json` - Report generation, scheduling, and display
+- `errors.json` - Validation and API error messages
+
+#### English (`/frontend/src/locales/en/`)
+- Matching files for English fallback support
+
+### 3. Component Updates
+- **Dashboard.tsx** - Integrated useTranslation hook, replaced all strings
+- **QuickStartWizard.tsx** - Full translation of wizard flow
+- **Reports.tsx** - Translated all report-related UI elements
+- **Layout.tsx** - Added language switcher and translated navigation
+
+### 4. Features Implemented
+- **Language Switcher** - Dropdown in app header to switch between German/English
+- **Persistent Selection** - Language choice saved and restored on reload
+- **Complete Coverage** - All user-facing strings in specified components translated
+- **Consistent Terminology** - MinIO-specific terms properly translated
+
+### 5. Backend Email Template
+- Confirmed existing German email template meets requirements
+- No changes needed as it was already in German
+
+## Technical Details
+
+### Dependencies Added
+```json
+"i18next": "^23.7.6",
+"react-i18next": "^13.5.0", 
+"i18next-browser-languagedetector": "^7.2.0"
+```
+
+### Configuration
+- Default language: German (de)
+- Fallback language: English (en)
+- Namespaces: common, dashboard, quickWizard, reports, errors
+- Detection: Browser language, localStorage, navigator
+
+### Integration Pattern
+```typescript
+const { t } = useTranslation(['namespace1', 'namespace2']);
+// Usage: {t('namespace:key')}
+```
+
+## Testing Recommendations
+1. Verify all translations display correctly
+2. Test language switching functionality
+3. Check translation persistence across sessions
+4. Validate email template generation
+5. Test error message translations
+
+## Future Enhancements
+- Add more languages (Spanish, French, etc.)
+- Implement date/time localization
+- Add number formatting based on locale
+- Create translation management workflow
+- Add missing translation detection
+
+## Conclusion
+The German translation implementation is complete and ready for production use. All requested components have been successfully translated while maintaining the application's functionality.