feat: Agent Demo

[YousefED]

Summary

This PR includes a proof of concept project where BlockNote AI is integrated with a Chat Sidebar (click the icon in bottom right). This makes it possible to: -- See a complete chat history -- See checkpoints and revert to those (wip) -- Ask generic questions about the document ("e.g.: summarize") instead of just using it as a writing-assistent -- Integrate with tools on the backend. For example, in the current demo you can ask it to look things up on the web. But, you could also connect to a Database / MCP / collection of documents, or add alternative tools like creating new documents.

Demo @ https://agent-demo.blocknotejs.org/

Rationale

Prototype / research

Changes

N/A

Impact

Testing

Screenshots/Video

Checklist

• [ ] Code follows the project's coding standards.
• [ ] Unit tests covering the new feature have been added.
• [ ] All existing tests pass.
• [ ] The documentation has been updated to reflect the new feature

Additional Notes