Deep CFR policy gradient fine-tuning 추가

tests/games/classic/test_deep_cfr_policy_gradient.py

@@ -0,0 +1,27 @@
+from __future__ import annotations
+
+from coolrl_lost_cities.games.classic.deep_cfr.encoding import input_dim
+from coolrl_lost_cities.games.classic.game import GameState, LostCitiesConfig
+
+from coolrl_lost_cities.games.classic.deep_cfr.networks import DeepCFRMLP
+from coolrl_lost_cities.games.classic.deep_cfr.policy_gradient import (
+    fine_tune_strategy_policy_gradient,
+)
+
+
+def test_policy_gradient_fine_tune_smoke() -> None:
+    config = LostCitiesConfig(seed=71)
+    state = GameState.new_game(config, seed=71)
+    network = DeepCFRMLP(input_dim(state), 2 * config.hand_size + 1 + config.n_colors, 16)
+
+    metrics = fine_tune_strategy_policy_gradient(
+        network,
+        config,
+        episodes=1,
+        seed=71,
+        max_steps=64,
+    )
+
+    assert metrics.episodes == 1
+    assert isinstance(metrics.avg_reward, float)
+    assert isinstance(metrics.loss, float)