Function ml__push_inference_observation_with_metadata 

pub unsafe extern "C" fn ml__push_inference_observation_with_metadata(
    context: InferenceHandle,
    id: u64,
    episode_state: u32,
    reward: f32,
    features_ptr: *const f32,
    features_len: u32,
    metadata_ptr: *const Metric,
    metadata_len: u32,
) -> ErrorCode

Pushes an observation with metadata into a queue to be used later.