Documentation: Sidebar Rules Menu/TOC grouping

[ststimac]

We should update the table of contents for the rules so that there is a sub-category, i.e. a11y, and then the grouping for those rules under than sub category.

If you're in the documentation looking at rules it's not a good user experience if you only want to be exploring a certain category but the menu of rules in the sidebar isn't group by category/doesn't explicitly state what category the rule is in/is listed alphabetically .

[ststimac]

I'm not sure how long this issue would take to do & what all needs to be done with the way the TOC currently gets pulled in.

We would be restructuring the table of contents to group hints by their main category. I think the ability to collapse different hint categories in the TOC would be helpful as well so there isn't just a massive list visible.

[ststimac]

Task list:

• group hints by parent hint category
• make accessible