Security Dashboard - Backend - Add filtering logic to SecurityMetricsResolver
## TL;DR
Add the `AttributeProjectResolver` service into `SecurityMetricsResolver` to filter vulnerabilities by security attributes, storing the filtered project IDs in the context.
## Acceptance Criteria
- [x] When feature flag is enabled and `security_attributes_filters` is provided, resolver calls `SecurityAttributesResolver`
- [x] When both `project_id` argument AND `security_attributes_filters` are provided, the intersection of project IDs is used
- [x] Filtering only applies to Group level
## Implementation Details
Technical specifics e.g. files to change, functions, API endpoints, or data model updates.
## Testing Approach
- [ ] Unit tests
- [ ] Integration tests
- [ ] Manual validation steps
## Estimate
issue