GLASS Flow for DiffusionNFT sampling

[julien-blanchon]

Look like a promising method for DiffusionNFT: https://arxiv.org/abs/2509.25170

I haven't see any implementation yet outside of the official one on a mockup example (checkboard): https://github.com/PeterHolderrieth/glass_flows_tutorial/blob/main/glass_flows_tutorial.ipynb