Site Editor: consider adding site title and site tagline to Identity section

[annezazu]

In the process of ensuring there's a global setting for site logo and site icon as part of this original issue #66241, I wanted to open up a new issue to build on the initial PR to consider adding in both site title and site tagline to this same section.

Here's roughly what this would feel like:

site.identity.more.mp4

Here's a visual:

The question is do we want to add this? In my mind, it adds a nice higher level view of keys details of the site and is reminiscent of the Customizer, which over the years of running the FSE Outreach Program I got feedback around folks missing. On the flip side, it could cause confusion if folks don't realize they are connected due to there being two places to update the same pieces. Let's discuss @jarekmorawski @poligilad-auto @WordPress/gutenberg-design @fabiankaegy @WordPress/outreach.

[annezazu]

PR here for anyone who wants to explore the look/feel of this too (I know that helps me): #76264