SvelteKit: Run function at route change (for access token, without doing it at a layout file)

I just started with SvelteKit and I have a question regarding functions, that should run on every route change. I did not find much, helpful information about it.

Just to run it at the layout files (which I do not prefer, because I might probably use multiple layout files and prefer one global place.)

In Vue.js, I do something like that, to check at every route change, if there is an access token (at the end of the router file):

// src/router/index.tsrouter.beforeEach((to, from, next) => {  AUTHENTICATION.default.fetchAccessToken();  if (to.options.protected && !AUTHENTICATION.default.tokenData) {    next("/");  } else next();});

How would I achive that in SvelteKit?

Would that work with svelte-routing in SvelteKit?... and is that in general a good idea, to check an access token?

Thank you in advance