Moving component descriptions into <Lede> removes descriptions from /components page

[yurm04]

Removing description from the component page metadata and using it directly in the <Lede>, we lose all the information on the /components root page. Imo it makes the page a bit inconsistent with the other ones that include descriptions on the grid (i.e., patterns page). This is not the intended outcome and we will need to re-add the descriptions to the /components url

Originally posted by @laurkim in #10214 (review)

Issue

Original

[jesstelford]

I'm wondering if the long descriptions are the correct ones to show on the preview cards?

I've seen this in other places too; the long description doesn't show enough information before it's truncated, effectively making it useless 🤔 There's also the issue with markdown; the description can contain arbitrary markdown which is why it's been pushed into the content instead of the frontmatter, but I think it makese more sense to have plain text in the preview cards.

We've already got a mechanism/types for setting a specific seoDescription in the frontmatter which will override the description frontmatter or firstParagraph auto generated value. Should we perhaps add a shortDescription option also?

That'd be a lot of work to write a short description for every component, so in the mean time I'll look at leveraging the seoDescription to get it showing on the preview cards.