- EngineManager now only exposes public SDK API (initialize, loadModel, pause/resumeRendering, getEngineComponent, destroy)
- Internal managers access Engine component directly via this.engineComponent getter on BaseManager
- Non-manager components use registry.engine3d.getEngineComponent() for direct Engine access
- Replaced getEngine() with onRawEvent()/offRawEvent() for raw engine event access
- Migrated 62 call sites across 13 files (9 managers, 1 panel, 3 toolbar buttons)
- Updated all architecture docs, API docs, and README to reflect new patterns
