fix: implement promote_operation_fallback for real and imag

Author: AayushSabharwal

src/interface.jl

@@ -120,6 +120,13 @@ function promote_operation_fallback(
     )
 end
 
+function promote_operation_fallback(
+    ::Union{typeof(real),typeof(imag)},
+    ::Type{Complex{T}},
+) where {T}
+    return T
+end
+
 """
     promote_operation(op::Function, ArgsTypes::Type...)