Update global.json to use .NET 9.0 SDK for GitHub Codespaces compatibility

Co-authored-by: eiriktsarpalis <[email protected]>

Author: Copilot

global.json

@@ -1,7 +1,7 @@
 {
   "sdk": {
-    "version": "10.0.100-rc.1",
-    "rollForward": "minor",
+    "version": "9.0.100",
+    "rollForward": "latestFeature",
     "allowPrerelease": true
   }
 }