ProgressionRoot autoload builds the JSON stores from
GlobalizePath("user://"), loads the Profile, reads the authored upgrade
tables into a SkillCatalogue, and owns the ProgressionService. Every
mutating operation is wrapped so draining and republishing cannot be
forgotten - the one risk of the DrainEvents design, now confined to one
file.
ProgressionEventRepublisher turns domain records into EventBus signals
(ADR-0004), so existing subscribers and scene wiring keep working. New
RunEnded signal: GameOverScreen reads Lives directly today, which is the
last-life soft-lock.
Registered after SkillManager, since the skill catalogue is built from
AvailableSkills. GameStateStore stays until slice 10 moves the callers.
Transitional: LevelStarted is republished with a catalogue index because
GhostManager names files ghost_level_{index}.json.
