Add reference to Spark 2.0 preview in README

Author: asundqui

README.md

@@ -26,6 +26,16 @@
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+> ## Spark 2.0 Preview
+> 
+> Spark 2.0 Developer Preview is now available!
+> - [Read the docs](https://sparkjs.dev/2.0.0-preview/docs/)
+> - [Check out the preview branch](https://github.com/sparkjsdev/spark/tree/v2.0.0-preview)
+> 
+> Version 2.0 is a major rewrite of the renderer to enable huge worlds made of dynamic 3D Gaussian Splats. It's a complete solution for creating, streaming, and rendering huge 3DGS worlds on the web on any device. It is mostly backward compatible with with Spark 0.1.*.
+> 
+> Read about all the [New Features in 2.0](https://sparkjs.dev/2.0.0-preview/docs/new-features-2.0/), learn how to migrate in our [1.0 → 2.0 Migration Guide](https://sparkjs.dev/2.0.0-preview/docs/0.1-2.0-migration-guide/), and get started quick with our [Level-of-Detail system](https://sparkjs.dev/2.0.0-preview/docs/lod-getting-started/).
+
 ## Features
 
 - Integrates with THREE.js rendering pipeline to fuse splat and mesh-based objects