fix(hf): serve lobby at root, ship built frontend, honor proxy headers
DeltaZN
6c64b04
- Mount the Gradio lobby at / and remove the /connect redirect (the
https->http redirect downgrade behind HF's proxy caused a white screen).
- Add ProxyHeadersMiddleware so the app trusts X-Forwarded-Proto from HF's
TLS-terminating proxy instead of emitting http:// absolute redirects.
- Build the React SPA with base /world/ so its assets live under /world/assets
(served by the /world catch-all), freeing /assets for the lobby's own bundle.
- Commit dist/frontend so the Space (which does not run npm build) can serve
the /world observer; un-ignore dist/frontend accordingly.
