Improve isRunning() implementation for OrchestrationMetadata

Currently, isRunning() relies on the name, instanceId, and runtimeStatus parsed from the OrchestrationState returned over gRPC to determine whether the orchestration is running, however, there is also an Exists field on OrchestrationState that should also be considered, as runtimeStatus is populated from an enum with a default value.

This may also affect the implementation of isCompleted() and/or isInstanceFound()

Repérez OrchestrationMetadata et ses points d’entrée isRunning(), isCompleted() et isInstanceFound(), puis suivez la manière dont OrchestrationState est reçu via gRPC. Vérifiez comment le champ Exists et le runtimeStatus par défaut sont actuellement gérés, et ajoutez ou mettez à jour les tests afin que les méthodes concernées distinguent correctement les orchestrations existantes des orchestrations inexistantes.