Chore: #555 handle PHP 8.4 deprecation

Closes #555 (closed).

handle "Passing 'E_USER_ERROR' to 'trigger_error()' is deprecated since PHP 8.4" deprecation, show separate examples in demo since throwing now halts execution and prevents subsequent rendering

See https://www.php.net/manual/en/errorfunc.constants.php#constant.e-user-error