refactor(vm): use SDK action constants instead of string literals

Replace hardcoded action strings with verda.ActionStart,
verda.ActionShutdown, verda.ActionDelete, etc. throughout
shortcuts, action map, and batch code.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hi-lei

internal/verda-cli/cmd/vm/action.go

@@ -15,12 +15,12 @@ import (
 
 // actionNameMap maps CLI flag values to action labels.
 var actionNameMap = map[string]string{
-	"start":          "Start",
-	"shutdown":       "Shutdown",
-	"force_shutdown": "Force shutdown",
-	"force-shutdown": "Force shutdown",
-	"hibernate":      "Hibernate",
-	"delete":         "Delete instance",
+	verda.ActionStart:         "Start",
+	verda.ActionShutdown:      "Shutdown",
+	verda.ActionForceShutdown: "Force shutdown",
+	"force-shutdown":          "Force shutdown", // CLI alias (hyphenated)
+	verda.ActionHibernate:     "Hibernate",
+	verda.ActionDelete:        "Delete instance",
 }
 
 // instanceAction defines a supported action with its display label and executor.
@@ -310,7 +310,7 @@ func runAction(cmd *cobra.Command, f cmdutil.Factory, ioStreams cmdutil.IOStream
 // runDeleteAgent handles delete in agent mode: requires --yes, deletes all volumes.
 func runDeleteAgent(ctx context.Context, f cmdutil.Factory, ioStreams cmdutil.IOStreams, client *verda.Client, inst *verda.Instance, yes bool) error {
 	if !yes {
-		return cmdutil.NewConfirmationRequiredError("delete")
+		return cmdutil.NewConfirmationRequiredError(verda.ActionDelete)
 	}
 
 	// In agent mode, delete the instance and all attached volumes.
@@ -330,7 +330,7 @@ func runDeleteAgent(ctx context.Context, f cmdutil.Factory, ioStreams cmdutil.IO
 
 	result := map[string]any{
 		"id":              inst.ID,
-		"action":          "delete",
+		"action":          verda.ActionDelete,
 		"status":          "completed",
 		"volumes_deleted": len(volumeIDs),
 	}

internal/verda-cli/cmd/vm/batch.go

@@ -192,7 +192,7 @@ func runBatchDelete(cmd *cobra.Command, f cmdutil.Factory, ioStreams cmdutil.IOS
 	}
 
 	if f.AgentMode() {
-		return writeBatchAgentOutput(ioStreams, f.OutputFormat(), "delete", instances, results)
+		return writeBatchAgentOutput(ioStreams, f.OutputFormat(), verda.ActionDelete, instances, results)
 	}
 
 	_, _ = fmt.Fprint(ioStreams.Out, formatBatchResults("Delete", instances, results))

internal/verda-cli/cmd/vm/shortcuts.go

@@ -22,22 +22,22 @@ var shortcuts = []shortcutDef{
 	{
 		Use:    "start <instance-id>",
 		Short:  "Start a VM instance",
-		Action: "start",
+		Action: verda.ActionStart,
 	},
 	{
 		Use:    "stop <instance-id>",
 		Short:  "Stop a VM instance",
-		Action: "shutdown",
+		Action: verda.ActionShutdown,
 	},
 	{
 		Use:    "shutdown <instance-id>",
 		Short:  "Shutdown a VM instance",
-		Action: "shutdown",
+		Action: verda.ActionShutdown,
 	},
 	{
 		Use:    "hibernate <instance-id>",
 		Short:  "Hibernate a VM instance",
-		Action: "hibernate",
+		Action: verda.ActionHibernate,
 	},
 	{
 		Use:     "delete <instance-id>",
@@ -110,7 +110,7 @@ verda vm %s --all --status offline --with-volumes --yes`, name)
 
 func exampleStatus(action string) string {
 	switch action {
-	case "start":
+	case verda.ActionStart:
 		return "offline"
 	case verda.ActionDelete:
 		return "offline"