Refactor the repo, and new docs styling

[Archmonger]

• Refactors the repo structure to match reactpy-django
• Update styling/formatting of the docs

This PR is mostly folder and CI workflow reorganization. The the docs still need an overhaul, and the source code needs refactoring to match react-router better.

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[Archmonger]

@rmorshea Can you provide me merge permissions for this repo?

[Archmonger]

@rmorshea I still don't have permissions to change required workflows.

[rmorshea]

Looks like we're missing coverage enforcement from the tests.

[Archmonger]

Will work on that now. On a related note, I've been debating whether we should drop black and instead rely strictly on the ruff formatter.

[Archmonger]

Will merge this one with the coverage fixes. Let me know your opinion on pulling out black from our repos and relying solely on ruff.