Make index pages consistent

[alexandratran]

Ensure index and category pages are as consistent as possible. This may mean have section overviews on all index pages or removing existing ones.

[joaniekube]

Started to assess this, but put this on hold to working on another issue. Will return to this when the Starknet MVP work is done.

So far we have this doc that outlines which sections use an index page:

• https://docs.google.com/spreadsheets/d/1uZZrBAtU2K2kchd3R4hab-BkHifbw4I9szq3CzSy07Q/edit?gid=0#gid=0

To do:

• [ ] Identify which are autogenerated index pages
• [ ] Get team consensus on what we would like to do for consistency.