Improve Styles > Typography panel

[richtabor]

Quite a few additions have been added to the Styles > Typography panel, but these changes were done in a piecemeal manner rather than following a cohesive plan.

Now that we have these pieces in place, let's explore how to clean up this panel and make it much more useful as a key component of styling a site's typography.

Tasks

• Reduce duplication of font library group headings #63502
• Remove "Manage fonts" button from Typography panel in favor of existing UX to open the Font Library (backtracking on Fixed some Embed's width in the editor. #6212).
• Use proper 40px height for all items within all ItemGroups. Fix item font family item height in the sidebar #63125
• Apply proper spacing <VStack spacing={ 5 }> between "Theme" and "Custom" font groups.
• Figure out something better for font size presets. The current control on the panel is duplicative.

Current

[richtabor]

Also relevant (if the groupings are reverted): #63505

[richtabor]

Remove "Manage fonts" button from Typography panel in favor of existing UX to open the Font Library (backtracking on #6212).

A potential path:

• "Add fonts" uses the same style as "Add background image" and related buttons.
• The vertical ellipsis icon becomes a popover for additional affordances for intent.

[akasunil]

#63125 would fix Use proper 40px height for all items within all ItemGroups.