Fix PHPDoc annotation to use @param instead of @var for model parameter

Author: OskarStark

src/agent/src/Agent.php

@@ -42,10 +42,10 @@
     /**
      * @param InputProcessorInterface[]  $inputProcessors
      * @param OutputProcessorInterface[] $outputProcessors
+     * @param non-empty-string $model
      */
     public function __construct(
         private PlatformInterface $platform,
-        /** @var non-empty-string */
         private string $model,
         iterable $inputProcessors = [],
         iterable $outputProcessors = [],