#[WithSpan] with SpanKind consts

Describe your environment
PHP 8.2.29 (from php:8.2-apache-bullseye docker image)

php --ri opentelemetry

opentelemetry

opentelemetry hooks => enabled
extension version => 1.2.1

Directive => Local Value => Master Value
opentelemetry.conflicts => no value => no value
opentelemetry.validate_hook_functions => On => On
opentelemetry.allow_stack_extension => Off => Off
opentelemetry.attr_hooks_enabled => On => On
opentelemetry.display_warnings => Off => Off
opentelemetry.attr_pre_handler_function => OpenTelemetry\API\Instrumentation\WithSpanHandler::pre => OpenTelemetry\API\Instrumentation\WithSpanHandler::pre
opentelemetry.attr_post_handler_function => OpenTelemetry\API\Instrumentation\WithSpanHandler::post => OpenTelemetry\API\Instrumentation\WithSpanHandler::post

composer show  | grep open-telemetry
open-telemetry/api                        1.8.0    API for OpenTelemetry PHP.
open-telemetry/context                    1.4.0    Context implementation for OpenTelemetry PHP.
open-telemetry/exporter-otlp              1.3.2    OTLP exporter for OpenTelemetry.
open-telemetry/gen-otlp-protobuf          1.5.0    PHP protobuf files for communication with OpenTelemetry OTLP collectors/servers.
open-telemetry/opentelemetry-auto-guzzle  1.2.1    OpenTelemetry auto-instrumentation for Guzzle.
open-telemetry/opentelemetry-auto-laravel 1.4.0    OpenTelemetry auto-instrumentation for Laravel
open-telemetry/opentelemetry-auto-psr18   1.1.1    OpenTelemetry auto-instrumentation for PSR-18 (HTTP Client).
open-telemetry/sdk                        1.12.0   SDK for OpenTelemetry PHP.
open-telemetry/sem-conv                   1.38.0   Semantic conventions for OpenTelemetry PHP.

Steps to reproduce

use OpenTelemetry\API\Instrumentation\WithSpan;
use OpenTelemetry\API\Trace\SpanKind;

#[WithSpan("foo", SpanKind::KIND_PRODUCER)]
private function foo()
{
  echo 1;
}

calls OpenTelemetry\API\Instrumentation\WithSpanHandler::pre with

$span_args = [
  "name" => "foo",
  "span_kind" => null,
];

What is the expected behavior?

$span_args = [
  "name" => "foo",
  "span_kind" => 3,
];

#[WithSpan("foo", 3)] works correctly, but #[WithSpan("foo", SpanKind::KIND_PRODUCER)] is wrong.

Start with OpenTelemetry\API\Instrumentation\WithSpan and WithSpanHandler::pre, then inspect how the SpanKind::KIND_PRODUCER attribute argument is resolved. Reproduce the example with PHP 8.2 and confirm that the handler receives span_kind as 3 rather than null; the literal 3 case provides a working comparison.