refactor: separate workload class from placement driver

internal/taskworker/worker.go

@@ -206,10 +206,11 @@ func (w Worker) launchSpec(assignment taskassignment.Assignment) (LaunchSpec, er
 func BackendMetadata(assignment taskassignment.Assignment) Metadata {
 	return Metadata{
 		Labels: map[string]string{
-			"ci.ddupan.top/runner":        "true",
-			"ci.ddupan.top/assignment-id": assignment.ID,
-			"ci.ddupan.top/task-id":       strconv.FormatInt(assignment.Task.GetId(), 10),
-			"ci.ddupan.top/backend":       string(assignment.Backend),
+			"ci.ddupan.top/runner":         "true",
+			"ci.ddupan.top/assignment-id":  assignment.ID,
+			"ci.ddupan.top/task-id":        strconv.FormatInt(assignment.Task.GetId(), 10),
+			"ci.ddupan.top/workload-class": string(assignment.Placement.Class),
+			"ci.ddupan.top/driver":         string(assignment.Placement.Driver),
 		},
 		Annotations: map[string]string{
 			"ci.ddupan.top/repository": assignment.Identity.Repository,

internal/taskworker/worker_test.go

@@ -53,9 +53,9 @@ func (t *fakeTasks) Report(_ context.Context, _ int64, phase Phase) error {
 
 func assignment() taskassignment.Assignment {
 	return taskassignment.Assignment{
-		ID:      "gitea-task-42",
-		Backend: taskassignment.BackendPod,
-		Task:    &runnerv1.Task{Id: 42},
+		ID:        "gitea-task-42",
+		Placement: taskassignment.KubernetesContainer,
+		Task:      &runnerv1.Task{Id: 42},
 		Identity: taskidentity.Identity{
 			Repository: "owner/repo",
 			Task:       "publish",