Add create_car_id_map to map v1 car IDs to v2 agent IDs for replay conversion

[chrisrca]

Add create_car_id_map to map v1 car IDs (1-8) to v2 agent UUIDs, enabling retrieval of v2 actions for v1 players during replay conversion with convert_game_state.

# Create the mapping from v1 car IDs to v2 agent IDs
id_map = create_car_id_map(frame.state.cars)
# Use the map to get v2 agent ID for a v1 player and retrieve actions
v2_id = id_map[v1_player.car_id]
action = frame.actions.get(v2_id, np.zeros(8, dtype=np.float32))