ML-DSA-44: use typed encoding/format parameters

Replace generic &pyo3::Bound<'_, pyo3::PyAny> with concrete
crate::serialization::Encoding/PrivateFormat/PublicFormat types
in private_bytes() and public_bytes() methods, consistent with
how other key backends are implemented.

Signed-off-by: Alexander Bokovoy <abokovoy@redhat.com>

Author: abbra

src/rust/src/backend/mldsa44.rs

@@ -123,8 +123,8 @@ impl MlDsa44PrivateKey {
     fn private_bytes<'p>(
         slf: &pyo3::Bound<'p, Self>,
         py: pyo3::Python<'p>,
-        encoding: &pyo3::Bound<'p, pyo3::PyAny>,
-        format: &pyo3::Bound<'p, pyo3::PyAny>,
+        encoding: crate::serialization::Encoding,
+        format: crate::serialization::PrivateFormat,
         encryption_algorithm: &pyo3::Bound<'p, pyo3::PyAny>,
     ) -> CryptographyResult<pyo3::Bound<'p, pyo3::types::PyBytes>> {
         utils::pkey_private_bytes(
@@ -202,8 +202,8 @@ impl MlDsa44PublicKey {
     fn public_bytes<'p>(
         slf: &pyo3::Bound<'p, Self>,
         py: pyo3::Python<'p>,
-        encoding: &pyo3::Bound<'p, pyo3::PyAny>,
-        format: &pyo3::Bound<'p, pyo3::PyAny>,
+        encoding: crate::serialization::Encoding,
+        format: crate::serialization::PublicFormat,
     ) -> CryptographyResult<pyo3::Bound<'p, pyo3::types::PyBytes>> {
         utils::pkey_public_bytes(py, slf, &slf.borrow().pkey, encoding, format, true, true)
     }