- Add ImageVulnerabilityScan and SbomArtifact models.
- Add ImageScannerService to download/install grype and syft into
/var/lib/serverkit/scanners, run CVE scans, generate SPDX SBOMs,
and enforce a configurable deploy gate.
- Add security API endpoints for scanner install, image scans,
scan history, deploy-gate checks, and SBOM create/download/list.
- Include lightweight image_scan badge in Application.to_dict() for UI.
- Add Alembic migration 018_image_scan_sbom.