When a block theme is active, cross-link from category management to site editor

[jameskoster]

In appropriate scenarios, it might be nice to offer a shortcut from category management to visual editing of said category.

Here's a mockup I put together last year that communicates the idea. It obviously needs some design updates :)

[mtias]

Also a link to the general category template from the main categories page.

[jameskoster]

Perhaps we no longer need the wp-admin version of category editing at all (Edit: when a block theme is active. Obviously we need it for classic themes).

Instead, clicking the category in the table above could just take you directly to the site editor, and there you can directly manipulate things like the description, assuming that the active theme includes that block in the template.

This would remedy a current UX issue in which folks edit the description and then don't understand why it doesn't appear on the frontend.

[jameskoster]

Closing in favor of #17099