* Add overridable hooks for sunk/reaped ball handling and turn behavior.
* Implement default scoring and game-over messaging across game modes.
* Add pretty game mode names for win-condition messages.
* Update Free Ball, Last Ball, and Snooker modes to return win-condition messages.
* Move the reset button lookup to the scene root for multiplayer setup.
* Move camera controller scene to shared base UI. Move parts of it to new game_data UI node.
* Add commented test state generation for end-state testing.
* add Free Ball game mode and lobby selection
* refactor base mode ball state tracking for reaped/sunk balls
* add player ownership tracking and colored-ball support
* add initial 9-ball mode implementation
* update 8-ball and snooker modes to use base ball handling
* replicate ball linear velocity for multiplayer synchronization
* improve ball collision sound propagation and physics settings
* reenable game music and initialize game signals
* improve lobby input focus and mode selection behavior
* adjust cue impulse origin and default game mode
