Very nice. This is a common pattern - Listing/Detail.
Will start a new thread if needed, but this felt like the same issue I am having.
Is it good practice to have sub pages here? It feels a little inefficient as, from what I can tell, you need to recall the API each time you go to a new page, despite having all the data on the listing.
You could show/hide with a detail section instead of a page redirect. But do you still need to call the API to get the data from the listing API object you clicked on?
Also, if you are using a button to navigate on a click action, am I understanding that the way to do it is to concatenate the site url (which may well change? Do I have to change every page nav if I go from a xxxx.toddle.dev site to a custom url) with the page path and the id of the slug.