feat: add count endpoint for users, enabling better pagination (#4848)

* Start on backend

* Hook up frontend

* Add to frontend test

* Add go test, wip

* Fix some test bugs

* Fix test

* Format

* Add to authorize.go

* copy user array into local variable

* Authorize route

* Log count error

* Authorize better

* Tweaks to authorization

* More authorization tweaks

* Make gen

* Fix test

Co-authored-by: Garrett <garrett@coder.com>

coderd/coderd.go

@@ -437,6 +437,7 @@ func New(options *Options) *API {
 				)
 				r.Post("/", api.postUser)
 				r.Get("/", api.users)
+				r.Get("/count", api.userCount)
 				r.Post("/logout", api.postLogout)
 				// These routes query information about site wide roles.
 				r.Route("/roles", func(r chi.Router) {