NestedFolders: Add library panels counting and deletion to folder registry (#69149)

* Expose library element service's folder service
* Register library panels, add count implementation
* Expand folder counts test
* Update registry deletion method interface
* Allow getting library elements from any folder
* Add test for library panel deletion
* Add test for library panel counting

pkg/services/ngalert/store/alert_rule.go

@@ -586,7 +586,7 @@ func (st DBstore) GetAlertRulesForScheduling(ctx context.Context, query *ngmodel
 }
 
 // DeleteInFolder deletes the rules contained in a given folder along with their associated data.
-func (st DBstore) DeleteInFolder(ctx context.Context, orgID int64, folderUID string) error {
+func (st DBstore) DeleteInFolder(ctx context.Context, orgID int64, folderUID string, user *user.SignedInUser) error {
 	rules, err := st.ListAlertRules(ctx, &ngmodels.ListAlertRulesQuery{
 		OrgID:         orgID,
 		NamespaceUIDs: []string{folderUID},

pkg/services/ngalert/store/alert_rule_test.go

@@ -474,7 +474,7 @@ func TestIntegration_DeleteInFolder(t *testing.T) {
 	}
 	rule := createRule(t, store, nil)
 
-	err := store.DeleteInFolder(context.Background(), rule.OrgID, rule.NamespaceUID)
+	err := store.DeleteInFolder(context.Background(), rule.OrgID, rule.NamespaceUID, nil)
 	require.NoError(t, err)
 
 	c, err := store.CountInFolder(context.Background(), rule.OrgID, rule.NamespaceUID, nil)