- Added AssignedUser interface with birthday and completed_at fields
- Updated Chore interface with assigned_users array and points field
- Added assigned_user_ids to CreateChoreRequest and UpdateChoreRequest
- Added query params to getChores: user_id and exclude_birthdays
- Added assignUsers method for POST /chores/{id}/assign endpoint
- Updated frequency enum to include 'on_trigger' and 'fortnightly'