Convert easy entrypoints files to Typescript (#30102)

package.json

@@ -167,6 +167,7 @@
     "@types/redux-immutable": "^4.0.3",
     "@types/requestidlecallback": "^0.3.5",
     "@types/webpack": "^4.41.33",
+    "@types/webpack-env": "^1.18.4",
     "@typescript-eslint/eslint-plugin": "^7.0.0",
     "@typescript-eslint/parser": "^7.0.0",
     "babel-jest": "^29.5.0",