feat(discovery): add Image and ServiceID fields to Job for swarm support

internal/discovery/discovery.go

@@ -15,6 +15,12 @@ type Job struct {
 	Service     string
 	WorkingDir  string
 	ConfigFiles []string
+	// Image is the full image reference the update request asked for.
+	// Compose jobs ignore it (compose.yml already pins the reference to
+	// pull); Swarm jobs need it to know what to set on the service spec.
+	Image string
+	// ServiceID is the Swarm service ID. Empty for Compose jobs.
+	ServiceID string
 	// Refused is true when the WorkingDir falls outside STACKS_ROOT.
 	// The job is returned so the caller can surface a per-job "refused"
 	// result, but it MUST NOT be executed.
@@ -74,6 +80,7 @@ func (d *Discovery) FindJobs(ctx context.Context, image string) ([]Job, error) {
 			Service:       cl.Service,
 			WorkingDir:    cl.WorkingDir,
 			ConfigFiles:   cl.ConfigFiles,
+			Image:         image,
 			Refused:       refused,
 			RefusedReason: reason,
 		})

internal/discovery/discovery_test.go

@@ -153,3 +153,20 @@ func TestFindJobs_NonComposeContainerIsSkipped(t *testing.T) {
 	require.NoError(t, err)
 	require.Empty(t, jobs)
 }
+
+func TestFindJobs_PopulatesImageField(t *testing.T) {
+	fake := &fakeDockerClient{containers: []types.Container{
+		mkContainer("registry.example.com/myapp:v1", mkComposeLabels(
+			"myapp-prod", "web",
+			"/home/shcizo/self-hosted/myapp-prod",
+			"/home/shcizo/self-hosted/myapp-prod/docker-compose.yml",
+			true,
+		)),
+	}}
+	d := discovery.New(fake, "/home/shcizo/self-hosted", "se.shcizo.auto-update")
+	jobs, err := d.FindJobs(context.Background(), "registry.example.com/myapp")
+	require.NoError(t, err)
+	require.Len(t, jobs, 1)
+	require.Equal(t, "registry.example.com/myapp", jobs[0].Image)
+	require.Empty(t, jobs[0].ServiceID)
+}