feat(block17): $CLAY simulated economy + single-match wagering

hf: adapt Dockerfile for HF Spaces, add entrypoint + migrate script

Phase 4.0–4.3: demo prep — auth, Elo fairness, rooms, lobbies, conversational entry, evolution

Patch Pass 2 Item 6: Kenji's opening repertoire + refresh script

hotfix: test_live_match player needs a username

Phase 3a: username login, character ownership, content rating, Alembic

Phase 2a hotfix: live gameplay works end-to-end

Phase 2a infra + tests + docs