fix(controller): 🐛 replace deprecated Request::get() with Request::input()

[chrillep]

This pull request replaces usages of the deprecated Request::get() method with Request::input() in CreateSecurityCookieController and DispatchEventFromAppController.

The Request::get() method has been deprecated in Symfony 7.4 (underlying Laravel's Request class) and will be removed in Symfony 8.0. Switching to input() resolves the deprecation warnings and aligns with Laravel best practices for retrieving input data.

References:

• https://symfony.com/blog/new-in-symfony-7-4-request-class-improvements
• Deprecation warning since symfony/http-foundation 7.4: for Request::get() laravel/framework#57962
• https://laravel.com/docs/12.x/requests#retrieving-an-input-value
• https://laravel.com/docs/11.x/requests#retrieving-an-input-value

Changes:

• CreateSecurityCookieController: Replaced $request->get('secret') with $request->input('secret').
• DispatchEventFromAppController: Replaced $request->get('event') and $request->get('payload') with $request->input(...).

closes #59