feat(doi): add DOI-based path access for commands

Support accessing repositories using DOI strings with optional subpaths
across ls, download, metadata, and file-metadata commands.

- Implement GET v3/doi/{id}/ API model and client calls
- Parse and resolve DOI paths into respective folder and files
- Extract common folder and file resolution logic to shared helpers
- Update README with example DOI-based shell commands

mdrsclient/commands/ls.py

@@ -54,9 +54,11 @@ class LsCommand(BaseCommand):
 
     @classmethod
     def ls(cls, remote_path: str, password: str | None, is_json: bool, is_recursive: bool, is_quiet: bool) -> None:
-        (remote, laboratory_name, r_path) = cls._parse_remote_host_with_path(remote_path)
+        remote = remote_path.split(":", 1)[0] if ":" in remote_path else ""
         connection = cls._create_connection(remote)
-        laboratory = cls._find_laboratory(connection, laboratory_name)
+        folder, laboratory = cls._resolve_folder(connection, remote_path, password)
+        laboratory_name = laboratory.name
+        files = cls._find_files(connection, folder.id)
         context = LsCommandContext(
             f"{remote}:/{laboratory_name}",
             connection,
@@ -66,8 +68,6 @@ class LsCommand(BaseCommand):
             is_quiet,
             is_recursive,
         )
-        folder = cls._find_folder(connection, laboratory, r_path, password)
-        files = cls._find_files(connection, folder.id)
         if context.is_json:
             cls._ls_json(context, folder, files)
         else: