Support navigating to hash URLs for in-page navigation

if supported, maybe hash / anchor / id navigation would look like this in user-land:

```ts
export default class Router extends EmberRouter {
location = config.locationType;
rootURL = config.rootURL;

constructor() {
super(...arguments);
this.on('routeDidChange', this.handleHashTarget);
}

willDestroy() {
this.off('routeDidChange', this.handleHashTarget);
}

@action
handleHashTarget() {
schedule('afterRender', () => later(this, 'scrollToId', 16));
}

@action
scrollToId() {
let id = this.location.hash;

if (id) {
document.getElementById(id)?.scrollIntoView();
}
}
}
```

(and then letting the actual router (router_js) handle `#` navigations. atm, the navigation look like:
```
Attempting URL transition to /my-route#hashId
Attempting URL transition to /my-route
```
It just drops the hash