Refactor endpoints to adhere to SOLID principles.

- Introduce `_extract_special_params` hook in `ListGetEndpointMixin`.
- Refactor `UsersEndpoint` and `RecordsEndpoint` to use the new hook, removing `_list_impl` overrides.
- Refactor `RecordsEndpoint` to share creation logic between sync and async methods via `_prepare_create_request`.
- Refactor `JobsEndpoint` to share path building and parsing logic between sync and async methods.
- Create `.jules/architect.md` to document architectural decisions.
- Remove unused imports in `imednet/endpoints/users.py`.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

Author: fderuiter

imednet/endpoints/users.py

@@ -1,9 +1,7 @@
 """Endpoint for managing users in a study."""
 
-from typing import Any, Awaitable, Dict, List, Optional, Union
+from typing import Any, Dict
 
-from imednet.core.paginator import AsyncPaginator, Paginator
-from imednet.core.protocols import AsyncRequestorProtocol, RequestorProtocol
 from imednet.endpoints._mixins import ListGetEndpoint
 from imednet.models.users import User