Admin Applications and Users pages are slow because of redundant GET /core/applications/

## What

admin Applications/Users pages are extremely slow because GET /core/applications/ does redundant work / stale planner stats.

## Want

- Admin Applications/Users pages are extremely slow because GET /core/applications/ does redundant work / stale planner stats

## Ideas this came from

- [#20829 GET /api/v3/core/applications/ takes 5-6s due to stale query planner statistics on small policy tables + redundant queryset evaluation](https://github.com/goauthentik/authentik/issues/20829) — GET /api/v3/core/applications/?onlywithlaunchurl=true takes 5–6 seconds for authenticated users on every request, even when the application-level policy cache i
- [#21570 admin interface: slow performance for applications and users](https://github.com/goauthentik/authentik/issues/21570) — In the admin interface, applications enlist slow, providers enlist fast. users enlist slow, groups enlist fast. It looks like database indexes are missing for a

Start by profiling GET /core/applications/ while loading the admin Applications and Users pages. Review the related context in issues #20829 and #21570, focusing on the reported redundant work and stale planner statistics. Done means those pages no longer exhibit the reported extreme slowness and the endpoint's redundant work is addressed.

Written by the indexing model from the issue text.