docs: @TaskAction
    public void deployAllAction() throws AppEngineException {
      List<Path> deployables = new ArrayList<>();
  
      // Look for app.yaml
      Path appYaml = stageDirectory.toPath().resolve("app.yaml");
      if (!Files.isRegularFile(appYaml)) {
        throw new GradleException("Failed to deploy all: app.yaml not found.");
      }
      addDeployable(deployables, appYaml);
  
      // Look for configuration yamls
      String[] validYamls = {"cron.yaml", "dispatch.yaml", "dos.yaml", "index.yaml", "queue.yaml"};
      for (String yamlName : validYamls) {
        Path yaml = deployExtension.getAppEngineDirectory().toPath().resolve(yamlName);
        if (Files.isRegularFile(yaml)) {
          addDeployable(deployables, yaml);
        }
      }
  
      // Deploy
      Deployment deploy = gcloud.newDeployment(CloudSdkOperations.getDefaultHandler(getLogger()));
  
      DeployConfiguration deployConfig = deployExtension.toDeployConfiguration(deployables);
      deploy.deploy(deployConfig);
    }