Add layout and styling for blueprint index page
Prior to these changes there was no summary list of blueprints. For individual blueprints, metadata like the author, DRIs, and current status were embedded in the content directly.
We are making these changes as part of the Next Architecture WG. See doc (internal only): https://docs.google.com/document/d/1n1pslXw6yeoqRmsWGi4VYu9bPg8k46IIXqdUTJR8HSU/edit#heading=h.6l73ofrhf8om
This MR introduces a new layout for blueprints including a summary view on the root index page as well as details for individual blueprint pages. See screenshots below:
Architecture Index Page
Blueprint Details Page
Review app:
- https://marshall-blueprints-index.docs.gitlab-review.app/ee/architecture/
- https://marshall-blueprints-index.docs.gitlab-review.app/ee/architecture/blueprints/work_items/
Also, closes #1301 (closed)
Edited by Achilleas Pipinellis