chore(tailwind): Small refactor for easier changes and ease of understanding

[gabrielmfern]

This was going to initially be address #1112, but I wasn't able to fix
it without first making improvements to the code's organization
because as it wasn't prioritized while we made the performance improvements
from before.

This does a few things to make the readability and organization a bit better:

• Separate the code for inlining styles and for getting them all from the elements into two "hook"s
  • Not exactly a hook since re-renders don't happen, so it might seem a bit off with the name,
    but, by a hook, I mean mostly following the general ways of creating and using them
    that makes the code a bit more familiar and easier to understand
• Don't replace the elements inside the array in place but rather, do a map over them
  • This is most of what was tripping me up with Tailwind doesn't recognize the Head component when NODE_ENV="production" #1112
• Process the Head as we're processing the elements
  • This, again, is very helpful for Tailwind doesn't recognize the Head component when NODE_ENV="production" #1112 as it paves the way for rendering the Head in deeper
    elements, like before.
• Separates the utils into different domains so that they're easier to find
• Adds a few more comments to places that are not so intuitive

How can I test/review this?

Most of the work we've put into writing our unit tests to make sure basic things
are still working properly already assure things are fine, so the tests passing is already
a thing that we can rest assured on.

As for reviewing, you can just look for the changes I mentioned before to make sure
they seem fine here, I'll try adding a few comments per line so that's easier to
understand to what portions I'm referring to.

[vercel]

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