Refactor the IfnexSettingsPage to use a custom Blade view and implement manual property binding for system settings. Additionally, localize navigation labels and groups to Persian for the Filament admin interface.
- Implement `ifnex-settings.blade.php` for custom settings management
- Localize navigation labels for Countries, Shipment Items, Shipments, and Shipping Rates
- Update navigation groups to Persian (تنظیمات, عملیات)
- Refactor `IfnexSettingsPage` to load settings from `SystemSetting` model during `mount`
- Fix type hinting for `ShipmentDirection` enum in `ShipmentResource` table columns