feat(images): gRPC client and server for ListImages

internal/machine/api/pb/docker.proto

@@ -152,6 +152,8 @@ message MachineImages {
   bytes docker_images = 2;
   // JSON serialised []image.Summary for images from containerd image store.
   bytes containerd_images = 3;
+  // True if Docker uses the containerd image store, false if it uses its internal image store.
+  bool docker_containerd_store = 4;
 }
 
 message CreateVolumeRequest {