Implement role and user management enhancements

- Added MaxIpLimit to roles, allowing for the configuration of simultaneous IP limits for users.
- Updated role creation and update commands to include MaxIpLimit, ensuring proper handling in the application logic.
- Enhanced user management by introducing a DELETE endpoint for user accounts, with appropriate checks to prevent self-deletion.
- Updated documentation to reflect changes in role and user management, clarifying the new IP limit functionality and user deletion process.
- Adjusted related tests to cover new functionality and ensure robust validation of role and user management features.

docs/api-design.md

@@ -130,8 +130,8 @@ status, createdAt }`. `expiresAt` всегда `null` (лимиты по сро
 | POST   | `/api/admin/activation-requests/{id}/approve`   | admin | —                        | `204 No Content` |
 | POST   | `/api/admin/activation-requests/{id}/reject`    | admin | `{ reason? }`            | `204 No Content` |
 | GET    | `/api/admin/roles`                              | admin | —                        | `RoleDto[]` |
-| POST   | `/api/admin/roles`                              | admin | `{ name, maxConfigs }`   | `RoleDto` |
-| PUT    | `/api/admin/roles/{id}`                         | admin | `{ maxConfigs }`         | `RoleDto` |
+| POST   | `/api/admin/roles`                              | admin | `{ name, maxConfigs, maxIpLimit }` | `RoleDto` |
+| PUT    | `/api/admin/roles/{id}`                         | admin | `{ maxConfigs, maxIpLimit }` | `RoleDto` |
 | DELETE | `/api/admin/roles/{id}`                         | admin | —                        | `204 No Content` (системные `admin`/`user` удалить нельзя) |
 | PATCH  | `/api/admin/users/{id}/role`                    | admin | `{ roleId }`             | `204 No Content` |
 
@@ -168,6 +168,7 @@ approve/reject над `ActivationRequest`.
 | PATCH  | `/api/admin/users/{id}/block`            | admin | —                            | `204 No Content` |
 | PATCH  | `/api/admin/users/{id}/unblock`          | admin | —                            | `204 No Content` |
 | POST   | `/api/admin/users/{id}/reset-password`   | admin | `{ newPassword }`            | `204 No Content` |
+| DELETE | `/api/admin/users/{id}`                  | admin | —                            | `204 No Content` (отзывает все конфиги пользователя в 3x-ui, затем удаляет учётку; себя удалить нельзя) |
 | GET    | `/api/admin/users/{id}/configs`          | admin | —                            | `VpnConfigDto[]` |
 | DELETE | `/api/admin/configs/{id}`                | admin | —                            | `204 No Content` (принудительный отзыв любого конфига) |
 | GET    | `/api/admin/stats`                       | admin | —                            | `StatsDto` |