Port 2.0 release notes to main (#21941)

The 2.0 release notes were created in the release branch (#21600), so I
have cherry-picked them back into main.

RELEASE_NOTES/2.0.0.md

@@ -0,0 +1,36 @@
+<!-- THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY. -->
+
+# Fluid Framework v2.0.0
+
+Fluid Framework 2 is now generally available and ready for production deployments! 🎉
+
+## New Features
+
+### 🌳 SharedTree DDS 
+
+In Fluid Framework 2, we're introducing a new DDS called SharedTree, a powerful and flexible DDS designed to keep
+hierarchical data synchronized between clients. We encourage you to move all new development and containers to
+SharedTree. We believe SharedTree is the best option for building with Fluid Framework 2. To learn more, visit the [SharedTree docs](https://fluidframework.com/docs/data-structures/tree/)
+
+Note: As a result of the new DDS, we have marked most pre-existing DDSes as Legacy (not deprecated yet), so you will
+have to update your import paths. Learn more about [API support levels](https://fluidframework.com/docs/build/releases-and-apitags/#api-support-levels) and our goal for a graceful [DDS deprecation](https://fluidframework.com/docs/data-structures/overview/#dds-deprecation)
+in future.
+
+
+### 📁 SharePoint Embedded Support 
+
+We are also introducing support for a new relay option in Fluid Framework 2, called SharePoint Embedded. This is a
+Microsoft 365 hosted service that keeps your collaborative Fluid data saved in a partition on SharePoint, allowing you
+to harness the power of Microsoft 365 file and document storage platform for you apps. You can integrate with SharePoint
+Embedded using the @fluidframework/odsp-client package. To learn more, visit the [SharePoint Embedded docs](https://aka.ms/fluid/spe)
+
+
+### 🩺 Fluid DevTools 
+
+Fluid Devleoper Tools is a browser extension that improves the developer experience when writing and debugging Fluid apps. It allows you to peek inside your application's Fluid container and diagnose issues. You can learn more about it in the [DevTools docs](https://aka.ms/fluid/devtool/docs)
+
+### 🛠️ Start Building Today! 
+
+And many more updates! Please continue to engage with us on GitHub
+[Discussion](https://github.com/microsoft/FluidFramework/discussions) and
+[Issue](https://github.com/microsoft/FluidFramework/issues) pages as you adopt Fluid Framework 2!