LatentSync (ByteDance) — vendored inference source.

Upstream:  https://github.com/bytedance/LatentSync
Commit:    a229c3948406bc2cf6eaf4873e662e70c6a04746  (2025-06-20)
Licence:   Apache-2.0 — see LATENTSYNC-LICENSE

What is here and why: `latentsync/` (the UNet, the lip-sync pipeline, the vendored
OpenAI Whisper audio encoder and their utilities), `scripts/inference.py` and the
`configs/` the entrypoint reads at runtime. Training scripts, the SyncNet configs,
the Gradio app, the demo assets and the evaluation corpus are not here.

Not cloned at install time, for the same reason the LongCat source is vendored: an
image someone else pulls has to run without network access to a third party. The
WEIGHTS are a separate matter and are fetched from the Hub on first use.
