Motion + agenda list: structure level is missing

[MSoeb]

Description: In the motion and agenda list, the structure level of users is not loaded until the participant list has been opened. This affects also the PDF export of motions.

Wrong: agenda item without structure level

Correct: agenda item with structure level

Wrong: Motion without structure level

Correct: Motion with structure level

Reproduction:

1. open a meeting
2. open participants > create user A with a structure level
3. open motions > create a motion, add user a as submitter and add the motion to the agenda.
4. open motion list again and reload the page. structure level is not visible anymore.
5. open agenda. reload page -> structure level is not visible anymore.
6. open motions > export the motion

What should happen:
The structure level should be visible in motion and agenda list without reloading the pages or opening the participant menu as first step. Additionally the pdf motion export should include the structure if one is available.