refactor(core): enhance SDK structure and documentation

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

examples/01_baas_flow.php

@@ -0,0 +1,40 @@
+<?php
+
+require_once __DIR__ . '/../vendor/autoload.php';
+
+use Apoloz\AlfaBank\AlfaBank;
+use Apoloz\AlfaBank\Enums\Environment;
+
+// 1. Initialize
+// Ensure you have valid certificates for the Sandbox
+$baas = AlfaBank::baas(
+    certificatePath: __DIR__ . '/certs/client.cer',
+    privateKeyPath: __DIR__ . '/certs/private.key',
+    environment: Environment::SANDBOX,
+    caBundlePath: __DIR__ . '/certs/russian_trusted_sub_ca.crt' // Mincifry
+);
+
+try {
+    echo "Authenticating...\n";
+    $baas->login(
+        clientId: 'your-client-id',
+        clientSecret: 'your-client-secret'
+    );
+    echo "Authentication Successful!\n";
+
+    // 2. Create a Beneficiary (Counterparty)
+    echo "Creating Beneficiary...\n";
+    
+    // In a real app, use the DTOs
+    // $payload = new CreateBeneficiaryRequestData(...);
+    // $baas->send(new CreateBeneficiaryRequest($payload));
+    
+    echo "Beneficiary Request Sent (Mock).\n";
+
+} catch (\Exception $e) {
+    echo "Error: " . $e->getMessage() . "\n";
+    if ($e instanceof \Apoloz\AlfaBank\Exceptions\AlfaBankException) {
+        echo "API Code: " . $e->getErrorCode() . "\n";
+    }
+}
+