Show today’s anniversaries (if any) from contacts
Looking at the database being opened by that SQLite snippet in Navicat I don't see any data there; I would assume that the iCloud move caused some changes but perhaps I am not viewing it right.

If you have a developer account you might look in the documentation for Address Book programming. There's pretty rich support for searching and I would be shocked if you couldn't look for matching dates. Anniversaries seem to not have their own distinct type - there's a property constant for kABBirthdayProperty but nothing like Anniversary, so it presumably falls under kABOtherDatesProperty.

kABOtherDatesProperty
Dates associated with a person (ABMultiDateProperty containing dates).
Available in OS X v10.3 and later.
Declared in ABGlobals.h.


And sure enough, there's an identifier (seemingly the only pre-provided identifier) for other dates.

Other Dates Labels
Labels for values contained in ABOtherDatesProperty multi-value properties.

kABAnniversaryLabe l
Constants
kABAnniversaryLabel
Anniversary date.
Available in OS X v10.3 and later.
Declared in ABGlobals.h.
Availability
Available in OS X v10.3 and later.


I imagine this sub-listing is why the command line app you reference doesn't spit out anniversaries; it would need to be cognizant of the possibility of other date types in that "other" category. But I would think it could be extended to handle them (if it still works?)

Given the above you might see if you can write a simple Swift app to spit out all entries with anniversaries. You can do command line apps with it. Applescript won't help you - the Contacts as interface doesn't seem to share out other type dates.