Add a "login to Front" page for internal KB links

This is for Knowledge Base when an admin is trying to share a link internally and a user is not logged in. Today, they see an error message and then need to navigate to Front to log in and then go find the link again. If a user is not logged in on their browser and they try to open an internal article link, they should simply be prompted to log in right away and then navigate directly to the article afterwards.