fix: preserve digest in image summary lookups

[ybelMekk]

What

• preserve tag@digest for image-based vulnerability lookups
• add regression tests for digest-bearing image refs
• add an integration test case using a digest-bearing image

Why

The API dropped the digest when looking up image summaries in V13S.

That caused refs like:

• image@sha256:abc
• image:tag@sha256:abc

to return:

• sbom.status = NO_SBOM
• vulnerabilitySummary = null

even when V13S had valid data for the full ref.

Changed

• internal/vulnerability/dataloader.go
• internal/vulnerability/queries.go
• internal/vulnerability/queries_test.go
• integration_tests/k8s_resources/vulnerability/dev/slug-1/app.yaml
• integration_tests/vulnerabilities.lua

[Copilot]

Pull request overview

This PR fixes V13S image vulnerability/SBOM lookups for digest-bearing image references by preserving the digest portion during lookups, and adds regression coverage via unit and integration tests.

Changes:

• Introduce splitImageRefForLookup to preserve tag@digest (or digest-only) for V13S lookups.
• Switch V13S lookups in the vulnerability dataloader and image vulnerability listing to use the new lookup-splitting helper.
• Extend unit/integration tests and fixtures to cover digest-bearing image references.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/vulnerability/dataloader.go	Uses digest-preserving image ref splitting when fetching image summaries from V13S.
internal/vulnerability/queries.go	Adds splitImageRefForLookup and updates image vulnerability listing to preserve digest in lookups.
internal/vulnerability/queries_test.go	Updates split tests and adds coverage for digest-preserving lookup splitting.
integration_tests/k8s_resources/vulnerability/dev/slug-1/app.yaml	Changes test workload image to include :tag@sha256:digest.
integration_tests/vulnerabilities.lua	Updates integration assertion to validate digest-preserved image tag and non-null vulnerability data.

[ybelMekk]

Måtte oppdatere prometheus, annars feilet mise:check