DM-30172: Define BFK tests for cp_verify

[czwa]

This adds catalog support to cp_verify, and then uses that to compare two ISR runs: one with and one without brighter-fatter correction. If the sizes trend in the correct direction, then the correction has improved things and is likely good.

[mfisherlevine]

People should be rewarded for leaving comments like this, rather than punished, but reading it I still can't really help but ask... so, what's the justification for these values? (sorry!)

[czwa]

NUM_MATCHES > 10 exists because we need to be able to trust the fit. In any real science image, this should be trivially met (the majority of my tests had ~200-300).
BRIGHT_SLOPE < -0.5 is entirely arbitrary. alpha must be negative (smaller size difference at larger magnitudes/fainter fluxes), but making it be simply negative ignores that the size change should be significant. If alpha =~ -0.01 we're essentially doing no correction. Every other constraint I can think if is circular, because it requires trying to figure out how much smaller the kernel should make things.
I am open to any suggestion on this.

[mfisherlevine]

Yeah, I don't really have any great suggestions, just had to comment on the comment really. Maybe just pasting this into a comment and replacing the # These values need justification. line would do it. And that way, if there's verifications failing in future, we can see that perhaps these values should be adjusted, as opposed to tests failing. (The other potential problem I can imagine is that if there's not much BF present in the first place (due to low depth in the observations, for example), or different sensors, (because we're camera-agnostic, haha), then this could cause a fail here, so noting that these values shouldn't be taken as gospel would be good).