Enhance app management with 'IsRecommended' feature

- Added 'IsRecommended' property to app-related data models, allowing apps to be marked as recommended.
- Updated API endpoints for creating and updating apps to include 'IsRecommended' in request bodies.
- Modified database schema to accommodate the new 'IsRecommended' field.
- Enhanced frontend components to display recommended apps with a star icon and updated forms to manage this property.
- Improved sorting logic in app listings to prioritize recommended apps.
- Updated documentation to reflect changes in API and data models.

docs/api-design.md

@@ -88,10 +88,14 @@ status, createdAt }`. `expiresAt` всегда `null` (лимиты по сро
 | ------ | -------------------------- | ----- | --------------------------------------------------------------------------------- | ------------- |
 | GET    | `/api/apps`                | user  | —                                                                                   | `Record<OsPlatform, ClientAppDto[]>` |
 | GET    | `/api/admin/apps`          | admin | —                                                                                   | `AdminAppDto[]` (вкл. выключенные) |
-| POST   | `/api/admin/apps`          | admin | `{ name, downloadUrl, operatingSystem, description?, iconUrl?, sortOrder }`        | `AdminAppDto` |
-| PUT    | `/api/admin/apps/{id}`     | admin | `{ name, downloadUrl, operatingSystem, description?, iconUrl?, sortOrder, isEnabled }` | `AdminAppDto` |
+| POST   | `/api/admin/apps`          | admin | `{ name, downloadUrl, operatingSystem, description?, iconUrl?, sortOrder, isRecommended }` | `AdminAppDto` |
+| PUT    | `/api/admin/apps/{id}`     | admin | `{ name, downloadUrl, operatingSystem, description?, iconUrl?, sortOrder, isEnabled, isRecommended }` | `AdminAppDto` |
 | DELETE | `/api/admin/apps/{id}`     | admin | —                                                                                   | `204 No Content` |
 
+`IsRecommended` — рекомендованные приложения идут первыми внутри своей группы ОС на `/api/apps`
+(сортировка `IsRecommended desc, SortOrder asc`, применяется после фильтра `IsEnabled`), помечаются
+значком-звездой на странице инструкций и в списке приложений в админке.
+
 `GET /api/apps` → пример (только `isEnabled == true`, ОС без приложений в ответе отсутствует):
 ```json
 {