Introduce a component-to-observer index to avoid iterating over all
observers for every world event. This optimizes event dispatching by
only notifying observers whose queries are relevant to the specific
component being added, removed, or changed.
Introduce `toJSON` and `fromJSON` methods to the `World` class to
allow saving and restoring world states. This requires components and
relationships to have human-readable names for stable serialization.
Introduces relationship management to the World, including
storage for forward and reverse relationships. Adds new observable
events and a `RelationshipUpdate` stream to track when relationships
are added or removed.
Initial implementation of an Entity-Component-System (ECS) featuring:
- Sparse set-based component storage for efficient access.
- Entity lifecycle management with generation-based recycling.
- Reactive query system using RxJS for change tracking.
- Batched event flushing to support frame-based updates.
- Type-safe component definitions via TypeScript inference.