Get Schedule Count

Report the retained schedule count and completion state for one session.

Args: schedule_id: Unique identifier of the session to inspect.

Returns: Current result count, requested limit, and whether enumeration is complete.

Raises: HTTPException: Status 404 when the session does not exist.

Behavior: This is a non-blocking snapshot: it neither awaits initialization nor acquires the generation lock. Completion is true after solver exhaustion or once the retained count reaches the requested limit. Access refreshes TTL.

ScheduleCountResponse(schedule_id='...', current_count=2, limit=10, is_complete=False)