Break the 281-line kitchen-sink schemas-misc.ts into 12 domain modules
(badges, automation, budget, wakeup, config-revisions, run-events,
agent-permissions, heartbeat, runtime-state, threads, participants,
subscriptions). schemas-misc.ts now re-exports the domain barrel so
existing imports keep working. Adds direct exports to contracts.ts for
new code to pull from the narrower modules.
