"""frontend/server — Gradio-served turn endpoint wrapping the finished backend engine.

Modules:
  session.py       GameSession: staged chaos -> one dispatcher call -> advance -> RenderState
  render_state.py  engine state -> schemas/render_state.schema.json dict (pure view)
  app.py           FastAPI app: POST /turn, POST /model, static SPA + sprites, gr.mount_gradio_app
  test_server.py   headless test driver (FakeLLM stub, schema validation, determinism)

The backend in /backend is CANON — these modules only import it (sys.path insert), never modify it.
"""