fix: apply NFC normalization to filenames and folder names sent to server

On macOS, local filenames and directory names may be in NFD encoding
(decomposed Unicode). Without normalization, files and folders are
created on the server with NFD names, inconsistent with the server's
NFC convention.

Apply normalize("NFC", ...) before sending names to the server in:
- FilesApi.create(): filename in multipart upload
- FilesApi.update(): filename in multipart upload
- UploadCommand: directory name in FoldersApi.create()

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

mdrsclient/commands/upload.py

@@ -2,6 +2,7 @@ import os
 from argparse import Namespace
 from concurrent.futures import ThreadPoolExecutor
 from typing import Any
+from unicodedata import normalize
 
 from pydantic.dataclasses import dataclass
 
@@ -81,7 +82,7 @@ class UploadCommand(BaseCommand):
                 if folder_map.get(d_dirname) is None:
                     d_folder = folder_map[d_parent_dirname].find_sub_folder(d_basename)
                     if d_folder is None:
-                        d_folder_id = folder_api.create(d_basename, folder_map[d_parent_dirname].id)
+                        d_folder_id = folder_api.create(normalize("NFC", d_basename), folder_map[d_parent_dirname].id)
                     else:
                         d_folder_id = d_folder.id
                     print(d_dirname)