Gate: Search Stages By UpdatedFrom Time

### Description

As a sharing member I want to query the newest business partner data in the input and output stages. Therefore, I want to query all business partners that have been changed after a given point in time.

The advantage of this functionality is that we can skip polling the changelog and directly poll the stages for new data.

### Acceptance Criteria

- [ ] [criteria 1]
- [ ] [criteria 2]
- [ ] [criteria 3]

### Additional Information

Start with the issue description for the sharing-member use case: querying business partners in input and output stages by a given UpdatedFrom time instead of polling the changelog. Define the missing acceptance criteria, including what qualifies as changed data and how completion will be verified; no files or tests are identified in the issue.

Written by the indexing model from the issue text.