Suggestion for List/Over folders.

[mechvel]

The master branch of July 19, 2025 has Data/Nat/ListAction.agda.

Probably better folder names will be

Data/List/OverSetoid.agda          -- items for lists over a setoid. Omit it if you prefer List/.../Setoid 
Data/List/OverDecSetoid.agda   -- Omit it if you prefer List/.../DecSetoid
Data/List/OverMagma.agda       -- for example, lists of magma elements form Magma, etc, also product is available  
Data/List/OverSemigroup.agda
Data/List/OverMonoid.agda
...
Data/List/OverNat.agda             -- lists over Nat have more items, special ones
Data/List/OverInteger.agda 

This looks systematic.