{
structure_level_id: Id; // required
list_of_speakers_id: Id; // required
initial_time: int;
}This action creates a new structure_level_list_of_speakers model with the given data. It is only
allowed if meeting/list_of_speakers_default_structure_level_time > 0. If initial_time is not
given, meeting/list_of_speakers_default_structure_level_time is used instead.
remaining_time is automatically set to initial_time.
The combination of (structure_level_id, list_of_speakers_id) must be unique in the meeting.
The request user needs list_of_speakers.can_manage.