Nest or group to-do items together

Who would benefit?

PMs, Product Ops, docs team,

What impact would it make?

Easier to use and navigate to-do lists within discrete phases

How should it work?

I'd like to be able to nest or group to-do checklist items under a higher-level checklist item. For example, I'd like to be able to do something like the following, where [ ] is a to-do checklist item and -- [ ] is a nested checklist item:

[ ] Alpha Requirements
-- [ ] Docs
-- [ ] Internal Enablement Sessions

[ ] Closed Beta Requirements
-- [ ] Add use-cases to docs
-- [ ] Create list of closed beta participants

And so on.