Create system notes for design events
What does this MR do?
This MR adds system note support for designs added to issues.
Does this MR meet the acceptance criteria?
- Changelog entry
- Documentation created/updated or follow-up review issue created
- Code review guidelines
- Merge request performance guidelines
- Style guides
- Database guides
- Separation of EE specific content
Performance and testing
This MR adds new DB activity to be performed on each design-management action including creation and modification. This will add some overhead to these calls, and increase the query count. At present these are unlikely to be a performance issue, but they may need to be moved to a background worker in the future.