The decoration scan read a mutable lexicon() aggregation during render
with no subscription, so a catalog settling or a child spawning after
prewarm left drafted tokens undecorated until an unrelated re-render.
The controller now publishes the aggregation as a snapshot store fed by
a new optional SlashSource.subscribeLexicon hook (ui-skill notifies on
settle/invalidate, ui-subagent forwards the session-list feed), the
composer keyboard face exposes it as an observable, and InputBar
subscribes through uSES. Sources registered after scope birth now warm
and join live controllers via a service broadcast.