Inheritance of workflow interfaces is not supported

  @WorkflowInterface
  public interface CustomerWorkflow {

    @WorkflowMethod
    void execute(Customer customer);

  }

  @WorkflowInterface
  public interface CustomerWorkflowWithSignal extends CustomerWorkflow {

    @SignalMethod(name = "setCustomer")
    void setCustomer(Customer customer);
  }

Registering two classes that implement the interfaces above should be possible, the second implementation should have a CustomerWorkflowWithSignal name.

Instead, it causes "java.lang.IllegalStateException: CustomerWorkflow workflow type is already registered with the worker".

Special consideration should be put into maintaining compatibility during the fix as it may change the workflow names for some users.

Start by reproducing the Java interface-registration example from the issue and trace how workflow names are derived and registered. The fix is complete when both implementations can register under the intended names, including CustomerWorkflowWithSignal, while preserving existing workflow names for compatible users; add regression coverage for the inheritance and compatibility cases.