Update icon (#159)

* light/dark mode?

* test

* fixed

* line break

Author: EItanya

README.md

@@ -1,7 +1,12 @@
 <div align="center">
-  <img src="img/icon.svg" alt="Autogen Framework" width="500">
+  <picture>
+    <source media="(prefers-color-scheme: dark)" srcset="https://raw.githubusercontent.com/kagent-dev/kagent/main/img/icon-dark.svg" alt="kagent" width="400">
+    <source media="(prefers-color-scheme: light)" srcset="https://raw.githubusercontent.com/kagent-dev/kagent/main/img/icon-light.svg" alt="kagent" width="400">
+    <img alt="kagent" src="https://raw.githubusercontent.com/kagent-dev/kagent/main/img/icon-light.svg">
+  </picture>
 </div>
 
+
 ---
 
 **kagent** is a kubernetes native framework for building AI agents. Kubernetes is the most popular orchestration platform for running workloads, and **kagent** makes it easy to build, deploy and manage AI agents in kubernetes. The **kagent** framework is designed to be easy to understand and use, and to provide a flexible and powerful way to build and manage AI agents.