Add a way to manually restore focus and scroll to hash element

Describe the problem

Sveltekit's router handles very well the focus and hash navigation, but it would be nice to be able to handle this manually sometimes using the same logic as the router.

Use case:

We have a page transition system at the agency where I work that delays the <slot> rendering in +layout.svelte until after the transition animation finishes (on outroend). All the router's focus and hash related code has already run by then, so we have to replicate that logic ourselves and run it after this animation to keep the navigation functioning properly.

Describe the proposed solution

Expose this logic in functions (or a single function that does both) that we can import (I don't really have any great ideas for naming right now).

import { restoreFocus, restoreHash } from '$app/navigation';

Alternatives considered

Replicate this logic in our own code.

Importance

would make my life easier

Additional Information

No response

Start by locating SvelteKit's router focus and hash-navigation logic and the $app/navigation entry point. Expose that existing behavior for manual use after delayed +layout.svelte slot rendering, and verify that focus restoration and hash scrolling still work after the transition.