docs: update readme

README.md

@@ -8,32 +8,9 @@
 
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-# Immutable Unity SDK Game Tutorial
+# Immutable Unity SDK Sample Game
 
-This repository includes the source code for the Unity tutorial, [Build a game with Unity](https://docs.immutable.com/docs/zkEVM/build-unity-game).
+This repository contains source code for the following:
 
-## Contributing
-
-Thank you for your interest in contributing to our project! Please share any feedback or suggestions by creating a GitHub issue.
-
-## Getting Help
-
-Immutable X is open to all to build on, with no approvals required. If you want to talk to us to learn more, or apply for developer grants, click below:
-
-[Contact us](https://www.immutable.com/contact)
-
-### Project Support
-
-To get help from other developers, discuss ideas, and stay up-to-date on what's happening, become a part of our community on Discord.
-
-[Join us on Discord](https://discord.gg/TkVumkJ9D6)
-
-You can also join the conversation, connect with other projects, and ask questions in our Immutable X Discourse forum.
-
-[Visit the forum](https://forum.immutable.com/)
-
-#### Still need help?
-
-You can also apply for marketing support for your project. Or, if you need help with an issue related to what you're building with Immutable X, click below to submit an issue. Select _I have a question_ or _issue related to building on Immutable X_ as your issue type.
-
-[Contact support](https://support.immutable.com/hc/en-us/requests/new)
+- **`step_XX` and `complete` branches**: Unity tutorial for building a game with Unity. Follow the tutorial at [Build a game with Unity](https://docs.immutable.com/docs/zkEVM/build-unity-game).
+- **`main` branch**: Code samples for implementing an in-game marketplace using the [Unity Orderbook](https://docs.immutable.com/sdks/zkEVM/unity/orderbook) and [zkEVM API](https://docs.immutable.com/sdks/zkEVM/unity/zkevm-api) packages.