Document the 9 head architectures and arena protocol

Add base_model: facebook/EUPE-ViT-B and link backbone in prose

Add arena runner for NYU Depth V2 screening with RMSE eval

Add tropical, compression, curvature, renormalization heads

Add novel heads: Optimal Transport (det), Info Bottleneck (seg), Harmonic Depth (depth)

7 depth head candidates with shared losses/utils and registry

Initial README

initial commit