Create rules engine job

Creates a new rules engine job, updates matching MZDB event statuses, and enqueues a RulesEngineJobCreatedEvent for publication. Publication is fire-and-forget via the internal message bus — a 201 response confirms the job was created and events were updated, but does not guarantee consumers have received the event. StampedCount reflects the number of events modified; SkippedCount reflects events that matched but were already in the target status.