Add demo GIF to README and documentation index

Author: rvxfahim

README.md

@@ -4,6 +4,11 @@ A demonstration project showcasing **CAN bus communication** between two ESP32 b
 
 ---
 
+<!-- Demo GIF: relative path so it renders both on GitHub and in the docs site -->
+<p align="center">
+   <img src="docs/demo.gif" alt="CAN demo" />
+</p>
+
 ## 🎯 What This Project Demonstrates
 
 1. **CAN Bus Communication**  

docs/demo.gif

@@ -2,6 +2,11 @@
 
 Welcome to the CAN Lecture RX/TX project documentation. This site covers how the project is structured, how to build and run it on the ESP32 boards, and how data flows through the system.
 
+<!-- Demo GIF shown in docs (relative path). File: docs/demo.gif -->
+<p align="center">
+	<img src="demo.gif" alt="CAN demo" />
+</p>
+
 ## Contents
 
 ```{toctree}