Use shared compact_dict helper for sync/async param building

Add a pure compact_dict helper and reuse it across TodoistAPI and TodoistAPIAsync to reduce duplicated None-filtering logic in request params/data preparation.

Author: goncalossilva

todoist_api_python/_core/utils.py

@@ -3,6 +3,7 @@
 import sys
 import uuid
 from datetime import date, datetime, timezone
+from typing import TypeVar
 
 if sys.version_info >= (3, 11):
     from datetime import UTC
@@ -43,6 +44,14 @@ def parse_datetime(datetime_str: str) -> datetime:
     return datetime.fromisoformat(datetime_str)
 
 
+V = TypeVar("V")
+
+
+def compact_dict(**values: V | None) -> dict[str, V]:
+    """Return a dictionary without keys whose value is `None`."""
+    return {key: value for key, value in values.items() if value is not None}
+
+
 def default_request_id_fn() -> str:
     """Generate random UUIDv4s as the default request ID."""
     return str(uuid.uuid4())