VBench metrics. Bootstraps upstream submodule on sys.path and installs runtime compat shims for modern torch/transformers/numpy/timm.
The upstream vbench source lives as a git submodule at fastvideo/third_party/eval/vbench (pinned to a specific Vchitect/VBench SHA). We do not pip-install it — we only need its Python modules importable. Its runtime deps (clip, transformers, etc.) are already in FastVideo's main env.
Compat with modern dependency versions is achieved at import time, in this file, instead of via on-disk patches to upstream files. Each shim below corresponds to a specific drift between vbench's pinned-2023 deps and FastVideo's current pins. Adding a new shim is preferable to editing the submodule.