docs: add localization page to mobile basics

resources/views/docs/mobile/3/the-basics/localization.md

@@ -0,0 +1,80 @@
+---
+title: Localization
+order: 600
+---
+
+NativePHP makes it easy to detect your user's locale and configure your app's supported languages.
+
+## Reading the device locale
+
+NativePHP reads localization data directly from the native operating system — not from the browser or web view. This
+gives you access to the user's true device-level language, region, and timezone settings.
+
+Use the `Device` facade to get the user's current localization settings at runtime:
+
+```php
+use Native\Mobile\Facades\Device;
+
+$loc = Device::localization();
+
+$loc->locale;             // "fr_FR"
+$loc->languageCode;       // "fr"
+$loc->regionCode;         // "FR"
+$loc->timezone;           // "Europe/Paris"
+$loc->currencyCode;       // "EUR"
+$loc->preferredLanguage;  // "fr"
+```
+
+This returns a `Localization` data object with the following properties:
+
+| Property            | Type   | Example            | Description                   |
+|---------------------|--------|--------------------|-------------------------------|
+| `locale`            | string | `en_US`            | Full locale identifier        |
+| `languageCode`      | string | `en`               | ISO 639 language code         |
+| `regionCode`        | string | `US`               | ISO 3166 region/country code  |
+| `timezone`          | string | `America/New_York` | IANA timezone identifier      |
+| `currencyCode`      | string | `USD`              | ISO 4217 currency code        |
+| `preferredLanguage` | string | `en`               | User's top preferred language |
+
+You can use this to set Laravel's locale to match the device:
+
+```php
+app()->setLocale($loc->languageCode);
+```
+
+## Configuring supported locales
+
+To ensure both platforms report accurate locale data, declare your app's supported locales in `config/nativephp.php`:
+
+```php
+'locales' => ['en', 'fr', 'es', 'de', 'ja'],
+```
+
+This is opt-in. If the array is empty or contains fewer than 2 entries, no build-time changes are made.
+
+<aside>
+
+#### Why is this needed?
+
+Without this configuration, iOS will only report a locale matching your app's declared development region — not the
+user's actual locale. On Android 13+, this also enables the per-app language picker in system settings.
+
+</aside>
+
+Use standard BCP 47 language tags. Region-specific codes like `pt-BR` or `zh-Hans` are also supported.
+
+## Putting it together
+
+```php
+// config/nativephp.php
+'locales' => ['en', 'fr', 'es'],
+```
+
+```php
+use Native\Mobile\Facades\Device;
+
+$loc = Device::localization();
+
+// Set Laravel's locale to match the device
+app()->setLocale($loc->languageCode);
+```