Nested Numbered Lists - increase distinction between top-level and secondary/tertiary numbers

[NMSalmon]

Feature Description

Currently, if you add an indent to an entry in a bulleted list, you get a different bullet symbol to distinguish top-level bullets from bullets nested beneath them. In contrast, numbered lists also have the ability to nest, but they use the same numbering format within the nested lists. In some contexts, this can be slightly confusing.

Would it be possible to change the defaults so that they proceed as follows (or offer a choice of formats?)
1.
--> a.
--> b.
[or]
1.
--> 1.1
--> 1.2
[or]
1.
--> 1a.
--> 1b.

Feature Use Case

This would be useful in contexts where folks are using more complex numbered lists, as it looks a bit neater and more precise. It also makes it easier for people to refer to specific sections of a text aloud in a classroom setting.

[SteelWagstaff]

This value comes from list-style-type. We'll need to check this value in McLuhan and confirm that it's being set as expected.