[image-list]: Add size field to json output

Sources/ContainerCommands/Image/ImageList.swift

@@ -111,7 +111,36 @@ extension Application {
             }
 
             if format == .json {
-                let data = try JSONEncoder().encode(images.map { $0.description })
+                var printableImages: [PrintableImage] = []
+                for image in images {
+                    let formatter = ByteCountFormatter()
+                    for descriptor in try await image.index().manifests {
+                        // Don't list attestation manifests
+                        if let referenceType = descriptor.annotations?["vnd.docker.reference.type"],
+                            referenceType == "attestation-manifest"
+                        {
+                            continue
+                        }
+
+                        guard let platform = descriptor.platform else {
+                            continue
+                        }
+                        var manifest: ContainerizationOCI.Manifest
+                        do {
+                            manifest = try await image.manifest(for: platform)
+                        } catch {
+                            continue
+                        }
+
+                        let size = descriptor.size + manifest.config.size + manifest.layers.reduce(0, { (l, r) in l + r.size })
+                        let formattedSize = formatter.string(fromByteCount: size)
+
+                        printableImages.append(
+                            PrintableImage(reference: image.reference, size: formattedSize, descriptor: image.descriptor)
+                        )
+                    }
+                }
+                let data = try JSONEncoder().encode(printableImages)
                 print(String(data: data, encoding: .utf8)!)
                 return
             }
@@ -160,6 +189,18 @@ extension Application {
             }
             try await printImages(images: images, format: options.format, options: options)
         }
+
+        struct PrintableImage: Codable {
+            let reference: String
+            let size: String
+            let descriptor: Descriptor
+
+            init(reference: String, size: String, descriptor: Descriptor) {
+                self.reference = reference
+                self.size = size
+                self.descriptor = descriptor
+            }
+        }
     }
 
     public struct ImageList: AsyncParsableCommand {