Sort Categories into Subgroups

Puzzle categories should be grouped under major categories in the selector for ease of use and backend improvement. For example, general categories like "Interlocking" act as the parent group for "Board Burr", "Burr", "Coordinate Motion" and "TIC". This has the added benefits of improving categorical search reliability and matching better the generally accepted mechanical puzzle categorization schemes used globally. See category layout here: https://docs.google.com/document/d/1oBdwkw25perWuMIxyUHANJSo_Al13p0Xixj_qijgkNU/edit?tab=t.0