docs: mention the VS Code extension in README #7

README.md

@@ -11,6 +11,10 @@ To use the online version, simply go to https://xschem-viewer.com/.
 
 You can add the URL of your `.sch` file to the end of the URL to load it directly, e.g. https://xschem-viewer.com/?file=https://github.com/RTimothyEdwards/sky130_ef_ip__rc_osc_500k/blob/main/xschem/sky130_ef_ip__rc_osc_500k.sch
 
+## VS Code Extension
+
+[Barak Hoffer](https://github.com/barakhoffer) maintains a VS Code extension of xschem viewer. You can get it at the [VS Code Marketplace](https://marketplace.visualstudio.com/items?itemName=barakh.vscode-xschem-viewer).
+
 ## Local Development
 
 ### Prerequisites