Introduce Single Directory Components

@pixelwhip @brentrobbins Please take a look at this initial pass at getting single directory components integrated into Prototype. Please let me know there are any issues. Here is the Merge request

Thanks so much for getting this started! After some additional discussion I've gone ahead and switched the 5.x branch to support the SDC components module as that is closer inline to what is being ported into Drupal Core. This needs additional review prior to the initial release of the 5.x-alpha branch.

Right on! Looks good to me.

Documenting conversations for visibility:

We will be creating a 5.0.x tag supporting SDC on D9 & then add a 5.1.x that supports D10, the only difference between these branches will be the difference of supported SDC & Core versions.

This will allow D9 sites that are not yet ready to move to D10 utilize SDC, however after November the 5.0.x branch will no longer be supported.

Thanks all for helping dig into the code and for your feedback!

The new initial 5.x branches have been released.