Staged spec maturation process proposal

Hi everyone,

As part of the discussion of a potential CG charter (start of thread over
at https://lists.w3.org/Archives/Public/public-swicg/2024Sep/0048.html ),
we should think about what a good structure would be for incubating specs,
notes, reports and other work items, and when and whether to graduate them
for considerations as specs, etc.

As P.L.H. mentioned the other week in this comment:
https://github.com/w3c/strategy/issues/435#issuecomment-2362285972 , we
might want to consider adopting the excellent staged approach that the
Federated ID CG/WG put together.

Bumblefudge made a copy of that staged process into a PR here:
https://github.com/swicg/potential-charters/pull/4

I'd love to also add this as a potential discussion item on the next call.

Dmitri