httpcaddyfile: Revise automation policy generation

[mholt]

This should fix a frustrating edge case where wildcard subjects are
used, which potentially get shadowed by more specific versions of
themselves; see the new tests for an example. This change is motivated
by an actual customer requirement.

Although all the tests pass, this logic is incredibly complex and
nuanced, and I'm worried it is not correct. But it took me about 4 days
to get this far on a solution. I did my best.

This is actually a better solution to b6686a5 I think.

[francislavoie]

"Hide whitespace changes" helped here, some of the blocks where somewhat misaligned in the diff because the tabulation was changed.

I don't think I have a 100% grasp on this, but I think it all makes sense.

👍

[mholt]

I don't think I have a 100% grasp on this,

Me neither tbh 😬

but I think it all makes sense.

Oh good! Because it doesn't for me 😅

Actually, so, it kinda makes sense, but it's just really really sensitive to changes, there's a lot of logic that is obvious to a human when writing a JSON config for automation policies, but that is hard to generalize into a correct algorithm.

[mholt]

Gonna merge this early and see if anyone using HEAD will report regressions as soon as possible.