feat: show local Docker images on project detail page

- Add GET /api/projects/{id}/images endpoint returning local images matching the project
- Add ListImagesByRef with tag, size, and created timestamp to Docker client
- Display images table on project page with tag, ID (truncated), size (MB), and created date
- Only shown when Docker is available and images exist locally

internal/docker/image.go

@@ -115,9 +115,11 @@ func EncodeRegistryAuth(username, password, serverAddress string) (string, error
 
 // LocalImage represents a Docker image on the local machine.
 type LocalImage struct {
-	ID   string `json:"id"`
-	Ref  string `json:"ref"`  // e.g., "registry/org/app:tag"
-	Size int64  `json:"size"` // bytes
+	ID      string `json:"id"`
+	Ref     string `json:"ref"`      // e.g., "registry/org/app:tag"
+	Tag     string `json:"tag"`      // just the tag part
+	Size    int64  `json:"size"`     // bytes
+	Created int64  `json:"created"`  // unix timestamp
 }
 
 // ListImagesByRef returns all local images matching a given image reference prefix.
@@ -132,10 +134,16 @@ func (c *Client) ListImagesByRef(ctx context.Context, imageBase string) ([]Local
 	for _, img := range result.Items {
 		for _, tag := range img.RepoTags {
 			if strings.HasPrefix(tag, imageBase+":") || tag == imageBase {
+				tagPart := ""
+				if idx := strings.LastIndex(tag, ":"); idx != -1 {
+					tagPart = tag[idx+1:]
+				}
 				images = append(images, LocalImage{
-					ID:   img.ID,
-					Ref:  tag,
-					Size: img.Size,
+					ID:      img.ID,
+					Ref:     tag,
+					Tag:     tagPart,
+					Size:    img.Size,
+					Created: img.Created,
 				})
 			}
 		}