docs: say that the tools can also be used individually

Author: koehlma

www/docs/the-rugix-project.md

@@ -7,6 +7,7 @@ sidebar_position: 5
 Rugix (formerly Rugpi) has been started out of frustration with the current state of the embedded Linux ecosystem.
 While many excellent tools are already available for building images, updating systems, and managing state, integrating them into a robust, coherent solution remains a significant challenge.
 The Rugix Project strives to **simplify the development of embedded Linux devices** by creating a unified, modern suite of development tools that seamlessly integrate to provide a streamlined and efficient workflow for building, updating, and managing embedded Linux systems.
+While the tools are designed to work together seamlessly, you can also use them individually, if you like.
 We believe that **building innovative devices shouldn't be as complicated as it often is today**.
 By lowering the amount of required engineering resources, we aim to foster innovation while reducing costs.