Use initial state for perfomance

Alternatively since the template list is a static array, the overhead to have an extra request seems rather high, it could be passed in as initial state on the page request

As discussed this might be a good exercise to learn the initial state API we have, could you give that a try in a follow up?

Originally posted by @juliusknorr in https://github.com/nextcloud/tables/issues/1808#issuecomment-2900140898

Example usage

JS dep is @nextcloud/initial-state, https://github.com/nextcloud/tables/blob/main/package.json#L36

In the backend, for example, we use it so far on one place to set the contextId from the backend: https://github.com/nextcloud/tables/blob/main/lib/Controller/PageController.php#L71 (and otherwise just provide the plain index page).

And here is that value loaded in vue: https://github.com/nextcloud/tables/blob/main/src/App.vue#L72