docs: add Git prerequisite note to Getting Started section

Author: Chris Khan

README.md

@@ -14,6 +14,8 @@ _Perp Dex As A Service - Powered by Injective_
 
 ## 📚 Getting Started
 
+**Prerequisites:** These instructions assume you have [Git](https://git-scm.com/downloads) installed.
+
 This repository is self‑contained and vendors the shared `injective-ui` layer, so you can run it without fetching external layers.
 
 ### 🚀 One-Click Setup (Recommended)