Add a comprehensive Chinese README (README‑cn.md) that explains the Capture‑the‑Flag game rules, setup instructions, and participant tasks.
Introduce a new backend script (backend/mypolicy.py) providing a basic world model, start_game, and plan_next_actions functions with simple flag‑assignment logic, serving as a starter implementation for the CTF challenge. This documentation and starter code help participants understand and begin developing their own algorithms.
