Fix game model tests: add host_id to GameHistory, use selectin loading for async safety

backend/app/models/models.py

@@ -212,6 +212,7 @@ class MTGOnlineGame(Base):
         "GamePlayer",
         back_populates="game",
         cascade="all, delete-orphan",
+        lazy="selectin",
     )
 
     def __repr__(self) -> str:
@@ -260,6 +261,7 @@ class GameHistory(Base):
     id = Column(Integer, primary_key=True, index=True)
     game_id = Column(Integer, ForeignKey("mtgonline_games.id"), nullable=True)  # Reference to original game
     room_id = Column(Integer, ForeignKey("mtgonline_rooms.id"), nullable=True, index=True)
+    host_id = Column(Integer, ForeignKey("mtgonline_users.id"), nullable=True, index=True)
     game_type = Column(String(50), nullable=False, default="Commander")
     winner_id = Column(Integer, ForeignKey("mtgonline_users.id"), nullable=True, index=True)
     duration_seconds = Column(Integer, nullable=True)