Overhaul test-packages setup

Author: dfreeman

package.json

@@ -2,10 +2,16 @@
   "private": true,
   "workspaces": [
     "packages/ember-css-modules",
-    "test-packages/embroider-app",
-    "test-packages/octane-addon",
-    "test-packages/octane-addon-with-module-name",
-    "test-packages/plugin-addon",
-    "test-packages/sass-app"
-  ]
+    "packages/ember-local-class",
+    "packages/glimmer-local-class-transform",
+    "test-packages/app-v1-ecm",
+    "test-packages/app-v1-elc",
+    "test-packages/app-v2",
+    "test-packages/addon-v1",
+    "test-packages/addon-v2"
+  ],
+  "volta": {
+    "node": "22.15.0",
+    "yarn": "1.22.22"
+  }
 }