Added attachment LinkButton

tests/Models/Attachments/Buttons/LinkButtonTest.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BushlanovDev\MaxMessengerBot\Tests\Models\Attachments\Buttons;
+
+use BushlanovDev\MaxMessengerBot\Enums\ButtonType;
+use BushlanovDev\MaxMessengerBot\Models\Attachments\Buttons\LinkButton;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+
+#[CoversClass(LinkButton::class)]
+final class LinkButtonTest extends TestCase
+{
+    #[Test]
+    public function toArraySerializesCorrectly(): void
+    {
+        $button = new LinkButton('Test Button', 'https://example.com');
+
+        $expectedArray = [
+            'url' => 'https://example.com',
+            'type' => ButtonType::Link->value,
+            'text' => 'Test Button',
+        ];
+
+        $resultArray = $button->toArray();
+
+        $this->assertSame($expectedArray, $resultArray);
+    }
+}