feat: display container images summary on Images tab (#83)

Add a new "Images" tab on the release details page that extracts
and displays all container images (including init containers) from
the release manifest. Images are grouped by image string and show
the associated resource and container name.

Closes #83

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pkg/dashboard/objects/data.go

@@ -139,6 +139,82 @@ func ParseManifests(out string) ([]*v1.Carp, error) {
 	return res, nil
 }
 
+// ContainerImage represents a container image found in a release manifest.
+type ContainerImage struct {
+	Resource string `json:"resource"`
+	Kind     string `json:"kind"`
+	Container string `json:"container"`
+	Image    string `json:"image"`
+}
+
+// ExtractImages parses a manifest and returns all container images found.
+func ExtractImages(manifest string) []ContainerImage {
+	dec := yaml.NewYAMLOrJSONDecoder(strings.NewReader(manifest), 4096)
+	var images []ContainerImage
+	for {
+		var tmp map[string]interface{}
+		if err := dec.Decode(&tmp); err != nil {
+			break
+		}
+		kind, _ := tmp["kind"].(string)
+		metadata, _ := tmp["metadata"].(map[string]interface{})
+		name, _ := metadata["name"].(string)
+
+		for _, podSpec := range findPodSpecs(kind, tmp) {
+			containers, _ := podSpec["containers"].([]interface{})
+			images = extractFromContainers(images, kind, name, containers)
+			initContainers, _ := podSpec["initContainers"].([]interface{})
+			images = extractFromContainers(images, kind, name, initContainers)
+		}
+	}
+	return images
+}
+
+func extractFromContainers(images []ContainerImage, kind, resource string, containers []interface{}) []ContainerImage {
+	for _, c := range containers {
+		cMap, ok := c.(map[string]interface{})
+		if !ok {
+			continue
+		}
+		img, _ := cMap["image"].(string)
+		cName, _ := cMap["name"].(string)
+		if img != "" {
+			images = append(images, ContainerImage{
+				Resource:  resource,
+				Kind:      kind,
+				Container: cName,
+				Image:     img,
+			})
+		}
+	}
+	return images
+}
+
+// findPodSpecs returns the pod spec(s) from a resource, depending on kind.
+func findPodSpecs(kind string, obj map[string]interface{}) []map[string]interface{} {
+	spec, _ := obj["spec"].(map[string]interface{})
+	if spec == nil {
+		return nil
+	}
+	switch kind {
+	case "Pod":
+		return []map[string]interface{}{spec}
+	case "Deployment", "StatefulSet", "DaemonSet", "ReplicaSet", "Job":
+		tpl, _ := spec["template"].(map[string]interface{})
+		if ps, ok := tpl["spec"].(map[string]interface{}); ok {
+			return []map[string]interface{}{ps}
+		}
+	case "CronJob":
+		jobTpl, _ := spec["jobTemplate"].(map[string]interface{})
+		jobSpec, _ := jobTpl["spec"].(map[string]interface{})
+		tpl, _ := jobSpec["template"].(map[string]interface{})
+		if ps, ok := tpl["spec"].(map[string]interface{}); ok {
+			return []map[string]interface{}{ps}
+		}
+	}
+	return nil
+}
+
 func (d *DataLayer) SetContext(ctx string) error {
 	if d.KubeContext != ctx {
 		err := d.Cache.Clear()