BoP's have existed since TOS, tho movie canon messed that one up too.
I was flying a klingon F5 frigate in 1983 when I got my copy of SFB (was NOT a BoP on any level), could it have been a raptor ?
Sorry, but you completely lost me now.
You wrote you didn't know before TNG that there were Raptors.
There were no Raptors in TNG.
The only Raptor that ever appeared anywhere was in "Enterprise" in the year 2002 episode "Sleeping Dogs".
I'm also not really sure what you mean by BoPs have existed since TOS, several novels that appeared after Star Trek 3 but play during the TOS era have them, sure.
The 1986 novel "The First Adventure" should be one of the first to feature one.
But I don't quite understand in what way movie canon got that wrong since the Bird of Prey Kruge uses is a familiar design to the Enterprise's crew so it was certainly not brand new to them.
And while the F5 could be something related, the F5 has a nearly trapezoid rear hull and the nacelles under the hull.
Of course it could be some kind of "TOS Raptor", but then the people from SFB could hardly have anticipated what the people who would make "Enterprise" would design some 20 years later.
And depending on the angle, the glowing green light from the original version of "Saturday's Child" could just as well be a Raptor.