Update devcontainer.json

.devcontainer/devcontainer.json

@@ -5,5 +5,19 @@
   "image": "mcr.microsoft.com/vscode/devcontainers/universal:latest",
 
   "remoteUser": "codespace",
-  "overrideCommand": false
+  "overrideCommand": false,
+
+ // Add the IDs of extensions you want installed when the container is created.
+ "customizations": {
+     "vscode": {
+         "extensions": [
+             "GitHub.copilot"
+         ]
+     },
+     "codespaces": {
+         "openFiles": [
+             "codespace.md"
+         ]
+     }
+ }
 }