Did you see what I did there?
Is this a rhetorical question? I think yes and no depending on the context like for example
He shot the ball right into the basket and exclaimed, "Did you see what I did there?"
I think this implies I was present (and witnessed) at the time of the happening and obviously saw the ball being shot
But on the other hand,
A little boy did a little trick and ran towards his mom who was sitting across the park and exclaimed "Mom did you see what I did there?"
But this this does not directly imply Mom being present there at the moment and does not make it obvious that she did or did not see what the little boy did there.
I encountered this question while reviewing negating-the-sentence type questions the question asked was
Did you see what I did there? (Negate)
Now if this was taken to be rhetorical, I could've just said
Didn't you see what I did there?
Notice this does not change the meaning of the sentence (because Didn't you see what I did there? is already rhetorical)
And if not, I will have to say
Did you not neglect what I did there?
This does not sound good so probably rhetorical? Or the negation is independent of what kind of question is posed.