Text this: Probing the electromagnetic structure of the $$P_c(4337)^+$$ P c ( 4337 ) + pentaquark: insights from a diquark–diquark–antiquark picture for $$J^P = \frac{1}{2}^-$$ J P = 1 2 - and $$\frac{3}{2}^-$$ 3 2 - states