feat: 10 funciones infra Docker y 2 tipos — operaciones de contenedores e imagenes

Funciones Docker: list/start/stop/remove containers, list/pull/remove images,
inspect, logs, run. Tipos: ContainerInfo e ImageInfo. Pre-existentes en el
dominio infra, ahora registrados.

functions/infra/docker_list_images.go

@@ -0,0 +1,45 @@
+package infra
+
+import (
+	"encoding/json"
+	"fmt"
+	"os/exec"
+)
+
+// DockerListImages lista las imágenes Docker locales.
+func DockerListImages() ([]ImageInfo, error) {
+	out, err := exec.Command("docker", "images", "--format", "{{json .}}", "--no-trunc").Output()
+	if err != nil {
+		return nil, fmt.Errorf("docker images: %w", err)
+	}
+
+	if len(out) == 0 {
+		return nil, nil
+	}
+
+	var images []ImageInfo
+	for _, line := range splitLines(out) {
+		if len(line) == 0 {
+			continue
+		}
+		var raw struct {
+			ID         string `json:"ID"`
+			Repository string `json:"Repository"`
+			Tag        string `json:"Tag"`
+			Size       string `json:"Size"`
+			Created    string `json:"CreatedAt"`
+		}
+		if err := json.Unmarshal(line, &raw); err != nil {
+			continue
+		}
+		images = append(images, ImageInfo{
+			ID:         raw.ID,
+			Repository: raw.Repository,
+			Tag:        raw.Tag,
+			Size:       raw.Size,
+			Created:    raw.Created,
+		})
+	}
+
+	return images, nil
+}