UI: per-env first-time tip banner on Play page (dismissable, localStorage-persisted)

UI: Home hero section explaining the demo; group partners by category in picker

API: simultaneous-env demo emits per-player frames; nicer Play game log (LBF/OC narration, mini-hanabi uses Hanabi log); hide empty difficulty pill; uploaded_partners endpoint + upload: kind in demo

UI polish: LBF caps, About page, GitHub nav link, UT orange accent

Initial jaxaht-benchmark deployment