fix: direct K8s scaling, replicas from K8s API, button labels, modify fetch

- Add ScaleClient using K8s API (like kubectl scale deploy --replicas=N)
  - ScaleDeployment: patch Deployment.Spec.Replicas directly
  - GetDeploymentReplicas: query actual K8s deployment replicas
  - Search by labels then fallback to deployment name match
- Wire ScaleClient to InstanceService via SetScaleClient in main.go
- ModifyModal: fetch full instance detail on open (list excludes values)
- InstanceCard: add text labels to action buttons (Entries/Diag/Modify/Delete)
  - Text visible on sm+ screens, icon-only on xs

backend/cmd/api/main.go

@@ -34,6 +34,7 @@ import (
 
 	"github.com/ocdp/cluster-service/internal/adapter/input/http/rest"
 	"github.com/ocdp/cluster-service/internal/adapter/output"
+	"github.com/ocdp/cluster-service/internal/adapter/output/k8s"
 	"github.com/ocdp/cluster-service/internal/bootstrap"
 	"github.com/ocdp/cluster-service/internal/domain/service"
 	"github.com/ocdp/cluster-service/internal/pkg/authz"
@@ -104,6 +105,7 @@ func main() {
 	)
 	instanceService.SetDiagnosticsClient(repos.DiagnosticsClient)
 	instanceService.SetTenantProvisioning(repos.WorkspaceRepo, repos.TenantKubeClient)
+	instanceService.SetScaleClient(k8s.NewScaleClient())
 
 	monitoringService := service.NewMonitoringService(
 		repos.ClusterRepo,