fix: add integration guide md file to help AI assistant's work (#2911)

### 🎯 Goal

Improve the experience for integrators who use AI code assistents, this
PR specifically helps with very vague commands like "integrate
stream-chat-react"

### 🛠 Implementation details

_Provide a description of the implementation_

### 🎨 UI Changes

_Add relevant screenshots_

Author: szuperaz