[feat] Re-enable player movement after crossing finish line #57
Description
Currently, player movement is disabled during the entire race and only re-enabled after all horses finish. We should allow the player to move freely once they cross the finish line, even if other horses are still racing.
This matches the legacy code behavior where:
- Player can move after crossing finish line
- Don't need to wait for other horses to finish
- Movement is re-enabled independently of race state