Add typescript-eslint-language-service (#30015)

webapp/package.json

@@ -50,6 +50,7 @@
     "sass-loader": "16.0.2",
     "strip-ansi": "7.1.0",
     "style-loader": "4.0.0",
+    "typescript-eslint-language-service": "5.0.5",
     "webpack": "5.95.0",
     "webpack-cli": "5.1.4",
     "webpack-dev-server": "5.1.0"