Replace beego/orm with dbx (#2693)

* Start migration to dbx package

* Fix annotations and bookmarks bindings

* Fix tests

* Fix more tests

* Remove remaining references to beego/orm

* Add PostScanner/PostMapper interfaces

* Fix importing SmartPlaylists

* Renaming

* More renaming

* Fix artist DB mapping

* Fix playlist updates

* Remove bookmarks at the end of the test

* Remove remaining `orm` struct tags

* Fix user timestamps DB access

* Fix smart playlist evaluated_at DB access

* Fix search3

server/auth.go

@@ -143,7 +143,7 @@ func createAdminUser(ctx context.Context, ds model.DataStore, username, password
 		Email:       "",
 		NewPassword: password,
 		IsAdmin:     true,
-		LastLoginAt: now,
+		LastLoginAt: &now,
 	}
 	err := ds.User(ctx).Put(&initialUser)
 	if err != nil {