feat(profile): add username + preferred_locale; wire to Inertia + middleware

- DB: users.username (unique), users.preferred_locale (default from app.locale)
- Backend: validation, model fillable; share supportedLocales; SetLocaleFromUser
- Frontend: profile page fields + types
- Filament: SuperAdmin profile page with username/language

feat(admin-nav): move Tasks to Bibliothek and add menu labels

fix(tasks-table): show localized title/emotion/event type; add translated headers

feat(l10n): add missing table headers for emotions and event types; normalize en/de files

refactor: tidy translations for tasks/emotions/event types

app/Filament/Resources/TaskResource/Pages/ManageTasks.php

@@ -15,11 +15,11 @@ class ManageTasks extends ManageRecords
         return [
             Actions\CreateAction::make(),
             Actions\Action::make('import')
-                ->label('Import CSV')
+                ->label(__('admin.common.import_csv'))
                 ->icon('heroicon-o-arrow-up-tray')
                 ->url(TaskResource::getUrl('import')),
             Actions\Action::make('template')
-                ->label('Download CSV Template')
+                ->label(__('admin.common.download_csv_template'))
                 ->icon('heroicon-o-document-arrow-down')
                 ->url(url('/super-admin/templates/tasks.csv')),
         ];