Update documentation and examples, add new nominal accounts features and authentication methods

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

examples/12_auth_code_flow.php

@@ -16,11 +16,24 @@ use Apoloz\AlfaBank\Requests\NominalAccounts\Beneficiaries\GetBeneficiariesReque
 
 // 1. Конфигурация
 $config = [
+    // CERTIFICATES:
+    // Production: You generated `private.key` and sent CSR to bank. Bank sent back `client.cer`.
+    // Sandbox: Bank sent you these via email/portal.
     'cert' => __DIR__ . '/certs/client.cer',
     'key' => __DIR__ . '/certs/private.key',
+    
+    // APP CREDENTIALS (OAUTH2):
+    // From: Developer Portal -> Your App -> Settings/Keys
+    // Note: If you don't have client_secret, generate it using `14_generate_client_secret.php`
     'client_id' => getenv('ALFA_BAAS_CLIENT_ID'),
     'client_secret' => getenv('ALFA_BAAS_CLIENT_SECRET'),
-    'redirect_uri' => 'https://your-app.com/callback', // Тот же, что указывали при получении кода
+    
+    // REDIRECT URI:
+    // Must match exactly what you entered in Developer Portal for this App.
+    'redirect_uri' => 'https://your-app.com/callback', 
+    
+    // BUSINESS DATA:
+    // From your Contract or Internet Bank. Not related to Auth directly.
     'account_number' => '40702810...'
 ];