Gate Artifact Registry UI controls with permission verdicts

Once gitlab-org/ops/artifact-registry#670 (closed) ships, the Artifact Registry UI must request include_permissions on the repository detail, repository list, and namespace endpoints, and render only the controls the verdicts allow. Today the UI shows every control and relies on server-side denial.

Verdicts are advisory: the UI hides or disables controls, it never makes an authorization decision. The server keeps enforcing.

Scope: the Vue UI reads the permissions objects from ArtifactRegistry::Client responses; per-action show/hide or disable on namespace and repository controls.

Blocked by gitlab-org/ops/artifact-registry#670 (closed).