Set max width in layout

[novellac]

Yikes! Briefly, what seems wrong?
We currently don't have a max width set on layout; we have been setting it in individual pages and I'd like to stop this (it's my fault for starting us down this road!).
🛑 Blocker: Once #120 is merged, I think we'll be in a better place to address this. #120 implements a header slot in the default layout, and this should allow us to style the content below the header.

Expected Behavior
Pages should (excluding the header and any CTAs) have a max width of TW large (1024px).

Current Behavior
Currently you must implement max widths on a per-page basis. 😬

Possible Solution
Add the max-width large to the default layout.

Steps to Reproduce
Compare the /dictionary page with the /about page. On the /dictionary page, no max width has been set. On the /about page, you can see a max width large.