A homing torpedo/release mechanism is not AI by the normal definition of the word. You're welcome to redefine words as much as you want but it's a bit silly. We also don't use that term for heatseekers or for line followers.

The 'signature' bit is interesting, but I'd still not label that AI, and neither does anybody else. It is a loitering munition, I'll give you that, and I think that that brings it closer to the 'mine' definition of things than the 'AI killbot'.