- Remove src/events/transport.ts; EventTransport now re-exported from
  @classytic/primitives/events via src/index.ts. Consumers importing
  DomainEvent/EventHandler/EventTransport from the media-kit root see
  no change.
- src/engine/create-media.ts imports EventTransport directly from
  primitives. Events helpers + in-process-bus updated for the primitives
  envelope field order; no wire-format drift.
- DevDeps: @classytic/primitives off file: link onto >=0.1.0 (npm).
- Test refresh: 373 tests across 27 files (was 355). Dropped obsolete
  tenant-field.test.ts after the 3.0 engine-factory split; real coverage
  moved into validators.test.ts + package-contents.test.ts.

Peer deps unchanged. No breaking API surface change for 3.0.x consumers.