Major updates to documentation

[pvandyken]

• Switch theme to furo
• Use snakebids 1.0 syntax for BidsDataset
• Update code blocks with line numbers and highlighting

Not quite finished yet, but I finished drafting the tutorial, so proofreads of that page should be appropriate if your able. Be sure to access the previous page via the actions console below to see the ui updates.

[pvandyken]

For the tutorial, I have still have to go over all the code blocks to make sure they are consistent, and check the line numbering and highlighting

[pvandyken]

Okay, I'm calling this ready. Documentation is a bit of a black hole for work, so it definitely could be improved still, but I think this is a good stopping point.

Changes:

• Use literalincludes almost exclusively within tutorial to make
  maintenance easier
• Update non-tutorial documentation files to 1.0 syntax
• Add more links to attributes like zip_lists and path
• Update typing annotations within source code for more consistency, and
  to take advantage of auto-documentation.
• Add instructions to download example dataset
• Various formatting fixes

[pvandyken]

Also updated the authors field within pyproject.toml

[kaitj]

Looks good to me, aside from the one comment.

Thanks for overhauling the documentation! 👏

EDIT: Forgot to mention I did notice there were some inconsistencies / typos from the portion of the docs being generated from the code. I don't think it is necessary for this PR, but we should go through and clean that up too at some point (or at least make corrections as see we see them).

[tkkuehn]

A couple of minor typos (I don't think I need to review it again) but this overall looks great to me, thanks for handling this!