fix: nested dtypes: export logical type in plugins (#13325)

crates/polars-ffi/src/version_0.rs

@@ -54,11 +54,15 @@ unsafe extern "C" fn c_release_series_export(e: *mut SeriesExport) {
 pub fn export_series(s: &Series) -> SeriesExport {
     let field = ArrowField::new(s.name(), s.dtype().to_arrow(), true);
     let schema = Box::new(ffi::export_field_to_c(&field));
-    let mut arrays = s
-        .chunks()
-        .iter()
-        .map(|arr| Box::into_raw(Box::new(ffi::export_array_to_c(arr.clone()))))
+
+    let mut arrays = (0..s.chunks().len())
+        .map(|i| {
+            // Make sure we export the logical type.
+            let arr = s.to_arrow(i);
+            Box::into_raw(Box::new(ffi::export_array_to_c(arr.clone())))
+        })
         .collect::<Box<_>>();
+
     let len = arrays.len();
     let ptr = arrays.as_mut_ptr();
     SeriesExport {