feat(cfn): add plugin

[georgettica]

this is the initial work, we can start discussing from here #580

[georgettica]

tests should not fail, I only added a new plugin, so maybe tests are flakey? something broken on master?

[kellyjonbrazil]

Nice - looks very clean! I was thinking along the same lines that we could add token types to the Ruamel YAML constructor.

Don't worry about the test failure - that's a behavior change in python 3.12 and 3.13 in the ipaddress library I need to address.

[georgettica]

good to know on the test bit :)

what I will say that to make this actually functional I need to write a good portion of boilerplate, because now I just "ignored" these objects.

also where there are two predicates scalar and sequence and it doesn't choose the right one it breaks and I don't know how to fix.

I am not a Ruamel master so this is me and a GPT of your choice's doing.

[kellyjonbrazil]

@georgettica I'm starting to work on the next release. Do you think this is close to being ready or should we hold off with this parser? Thanks!

[georgettica]

Let's hold off, just because I was waiting for another support / guidance.

I'll give it another push later at some point and let you know the status when I do