fix: remove non-existent validate script reference from root package.json

The validate script will be added in Task 15 when the full-validation.sh script is created. For now, remove it to prevent npm script execution errors.

package.json

@@ -9,8 +9,7 @@
   "scripts": {
     "dev:angular": "cd apps/angular && npm start",
     "dev:react": "cd apps/react && npm run dev",
-    "dev:both": "concurrently \"npm run dev:angular\" \"npm run dev:react\"",
-    "validate": "cd e2e && bash ../scripts/full-validation.sh"
+    "dev:both": "concurrently \"npm run dev:angular\" \"npm run dev:react\""
   },
   "devDependencies": {
     "concurrently": "^8.2.0"