Publish Firecamp project file for Integration API

[zehnm]

As an integration developer I'd like to have an easy way to interact with the API without writing code. This simplifies learning the API, exploring features and speeds up development.

AC:

• Firecamp project file for the WebSocket Integration API.
• Project file must contain examples of all mandatory messages.
• Project file should contain all optional messages which are at least in state 🔍 Api definition review.

Optional: check current WebSocket support in Postman if it reached a usable state. Since we'll release a Postman collection for the Core REST API, it would be convenient having everything in one tool.