优化 README.md

[timebug]

Auto-generated by AI Agent - Session ID: 694be961e9811f712f493347

---

Note

Updates README.md to provide a complete, user-friendly overview and setup guide.

• Adds project description, feature list (UCCI engine, opening book, Python UI), and board image
• Details requirements and explicit Python 2.7/pygame 1.9.x constraints
• Adds install/run steps for Linux/macOS (make && make install, python2 pycchess/cchess.py) and Windows (Conda/MSYS2/WSL)
• Documents usage: human vs AI, network mode flags (-nr, -nb), and controls (keyboard space)
• Adds engine-only UCCI interaction example for src/harmless
• Includes development commands (make, make install, make clean) and troubleshooting tips (SDL deps, verifying pygame, checking pycchess/harmless)
• Notes licensing for the Python UI (GPLv3)

^{Written by Cursor Bugbot for commit 40b3470. This will update automatically on new commits. Configure here.}