503371 / Create Vulnerability Scanner Filter

What does this MR do and why?

This MR creates a separate Scanner Vulnerability Report Filter by splitting it from the Tool filter. Before this change, we had both the Scanner and Report Type filters bundled under the Tool filter, which wasn't very clear for users.

A follow-up MR will rename the Tool filter to Report Type and remove all logic that currently handles the Scanner filter within it.

References

Related Issue: #515303 (closed) Main Parent Issue: #503371 (closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. In your Rails console, enable the feature flag by running: Feature.enable(:vulnerability_report_type_scanner_filter)
2. Open your browser and visit http://gdk.test:3000/gitlab-org/security-reports/-/security/vulnerability_report If no vulnerability reports appear, additional setup may be needed. Follow the steps here.
3. Look for the Scanner option when you open the Search/Filter menu. It should appear alongside other filter options.
4. After clicking Scanner, you'll see a list of available scanners you can filter by.
5. Pick any scanner from the list - you'll notice the Filter/Search updates to show "Scanner || [your selected scanner]":