로스트 시티 클래식 코어 이식

맥락:
- 새 레포의 첫 범위를 RL 없는 Lost Cities classic 게임 구현으로 잡았다.
- 기존 tier0-3 실험 축은 제거하고 classic 5-expedition 룰을 기본값으로 둔다.

변경:
- games/classic 아래에 Cython 게임 엔진, env, bots, backend 경계, Rust core와 proto schema를 이식했다.
- setuptools/Cython 빌드 설정과 package data, README, classic port notes를 추가했다.
- 룰, 점수, 마스크, env, canonical state, bot, Rust parity 테스트를 새 경로로 가져왔다.

확인:
- uv run pytest tests/games/classic
- uv run lost-cities-classic

README.md

@@ -0,0 +1,24 @@
+# coolrl-lost-cities
+
+Focused Lost Cities extraction from the legacy `coolrl` repository.
+
+The current implementation starts with the classic two-player card game:
+
+- classic 5-expedition rules by default
+- Python/Cython game engine
+- Rust core parity checks
+- env wrapper
+- random, passive-discard, and safe-heuristic bots
+- core rule, scoring, mask, env, canonical-state, bot, and Rust parity tests
+
+Training code, Deep CFR, learned-policy evaluation, GUI, and web client are
+intentionally outside the first port.
+
+## Development
+
+```bash
+uv run pytest tests/games/classic
+uv run lost-cities-classic
+```
+
+See [classic port notes](docs/classic-port-notes.md) for the current direction.