vue always throws a render error, even if we include a test for user.steeringUser
before comparing user.steeringUser.is_superuser.

so we moved it to the js logic and use a separat modules array for superusers

* deactivate superuser entries for standard users
* consistent naming

Our linting config in package.json was:
```
    "extends": [
      "plugin:vue/essential",
      "eslint:recommended"
    ],
```

Now switching to "plugin:vue/recommended" and apply all auto-fixes