Implement ALTCHA captcha service with challenge generation and solution verification

- Added AltchaService class for managing ALTCHA captcha challenges and solutions.
- Created CaptchaController to handle API requests for generating challenges.
- Introduced CaptchaGuard for validating captcha solutions on public endpoints.
- Developed unit tests for AltchaService to ensure challenge creation and solution verification functionality.
- Implemented integration tests for the Captcha API endpoint and captcha bypass behavior when disabled.
- Added documentation for the Captcha API in the corresponding markdown file.

src/Auth/Controller/PreRegistrationController.php

@@ -10,6 +10,7 @@ use App\Clinic\Entity\Clinic;
 use App\Clinic\Repository\ClinicRepository;
 use App\Doctor\Entity\Doctor;
 use App\Doctor\Repository\DoctorRepository;
+use App\Shared\Captcha\CaptchaGuard;
 use App\Shared\Constant\ErrorCodes;
 use App\Shared\Controller\BaseController;
 use App\Sms\Service\SmsService;
@@ -35,11 +36,14 @@ class PreRegistrationController extends BaseController
         private readonly SmsService                  $sms,
         private readonly LoggerInterface             $logger,
         private readonly string                      $appUrl,
+        private readonly CaptchaGuard                $captcha,
     ) {}
 
     #[Route('/api/v1/pre-registration', methods: ['POST'])]
     public function submit(Request $request): JsonResponse
     {
+        $this->captcha->assertValid($request);
+
         $data   = json_decode($request->getContent(), true) ?? [];
         $type   = trim($data['type']   ?? '');
         $name   = trim($data['name']   ?? '');