[Meta] Plan for Olivero subtheme

Fixed ul markup

Adding the first round of issues to create components for Experience Builder.

Adding design issues and prioritize component implementation issues.

Removing old list.

Except for XB components and the final 3 open bullets, it looks like:

✨ Custom styling for home page Active

is the only remaining item... @mherchel was/is looking at it today.

Added a link to the issue for implementing the Stats component.

Added link to FAQ/accordion implementation.