Simplify internal types

[trezy]

Description of change

All changes are related to typings

• PixiReactNode is now used for both internal and internal types (eliminated Instance types)
• PixiReactNode is now 1 type, rather than several
• All internal types use HostConfig where appropriate (instances, props, etc); this will make it easier to update these types in the future
• Event handlers are now explicitly typed with Pixi's FederatedEventHandler instead of usign a generic function signature with Federated* events
• Removed a bunch of unused types
• Updated names of several types to more accurately reflect their purposes

Pre-Merge Checklist

• Lint process passed (npm run lint)
• Tests passed (npm run test)

[github-actions]

🎉 This issue has been resolved in version 8.0.0-beta.3 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀