While BoT, Utter Dark, Astral Corruption and like should automatically void NAP, I do not see other spells end NAP unless specified clearly in NAP agreement. BoT and alike all directly damage other players (friendly or not). So it is considered offensive spell casted to your land. I do not see Arcane Nexus and especially FoA automatically end NAP. But you can always say that when you sign NAPs.
The point isn't which spells cause attacks on the person with whom you have a NAP. Rather it is spells that are so powerful that they provide overwelming advantage, such that the terms lof a longterm nap should immediately be cancelled.
So, for example if you have a nap+8, and you are the only neighbor of someone that casts forge - the duration of your NAP is untenable.
I will definitely add Astral Corruption to the list and utterdark to the list.
If you think FoA or AN are too powerful a spell for NAPs to continue, you should listed them when NAPs were agreed to. Otherwise, it is a breach of NAP and badboy points are assessed against you.
Forging chalice is impossible to confirm, in most cases. Aka, you can know its been forged, but you generally don't know who has it until a stack of tartarians shows up on your door step.