Module idea: a better knock-knock

[johndwells]

We often need to password-protect a site during development, and while there is this: https://github.com/verbb/knock-knock/

It has some shortcomings, namely that the login template is not at all customisable. And while it isn't too difficult to spin up a basic front-end login form for Craft users, it requires sharing a username/email and password, but typically during the development phase it's preferred to share a memorable and simple password only (so no username/email combo and no need to have a system user).

The boilerplate version could use cdn-hosted Tailwind that could likely be swapped out for a real site's tailwind with little customising necessary. It might also pair nicely with some boilerplate error pages... perhaps there is a possibility of sharing layouts?