Function ZL_Compressor_validate 

pub unsafe extern "C" fn ZL_Compressor_validate(
    compressor: *mut ZL_Compressor,
    starting_graph: ZL_GraphID,
) -> ZL_Report

@brief Validates a graph maintains basic invariants to reduce the chance of errors being triggered when compressing.

@note this operation is also integrated as part of ZL_Compressor_selectStartingGraphID(). This function is kept for backward compatibility.

@returns Success if graph is valid, error otherwise. @param starting_graph The starting graph to validate.