//! The partition orchestrator: vehicle continuity, admission, commit, recovery.
//!
//! One [`worker`] task owns each partition outright — its vehicle table,
//! scheduler and frontier tracker — with no cross-partition sharing, driving
//! each vehicle read → schedule → admit → dispatch → validate → commit →
//! advance frontier. Raw age is an observed freshness SLA, not a terminal
//! correctness condition. Draining is handled by [`lifecycle`](crate::lifecycle).