Improve README formatting and add demo video

Updated README to enhance formatting and add a demo section.

Author: Emanschi

README.md

@@ -5,7 +5,7 @@ It gradually displays text character by character, making it ideal for dialogue
 
 ---
 
-## Features
+## ➡️ Features
 - Simple setup with just a few lines of code  
 - Adjustable writing speed  
 - Optimized with `StringBuilder` for better performance  
@@ -24,6 +24,11 @@ By default, each character appears every **0.1 seconds**, but you can easily adj
 
 ---
 
+## ✅ How it looks
+![demo](README.gif)
+
+---
+
 ## 💻 Example Usage
 
 ```csharp