CLI-CAL-001/002/003/004/005/006/007/008/009/010: Add calendar command group and CRUD plan commands

- Add hf calendar command group to command surface and router
- Implement schedule/show/edit/cancel/date-list commands
- Implement plan-schedule/plan-list/plan-edit/plan-cancel commands
- Add leaf help for all calendar commands
- Align CLI with backend calendar routes and response envelopes
- Support virtual slot ids for edit/cancel
- Validate with go build and go test ./...

cmd/hf/main.go

@@ -190,6 +190,9 @@ func handleGroup(group help.Group, args []string) {
 	case "proposal", "propose":
 		handleProposalCommand(sub.Name, remaining)
 		return
+	case "calendar":
+		handleCalendarCommand(sub.Name, remaining)
+		return
 	case "comment":
 		handleCommentCommand(sub.Name, remaining)
 		return
@@ -700,6 +703,45 @@ func handleSupportCommand(subCmd string, args []string) {
 	}
 }
 
+func handleCalendarCommand(subCmd string, args []string) {
+	tokenFlag := ""
+	var filtered []string
+	for i := 0; i < len(args); i++ {
+		switch args[i] {
+		case "--token":
+			if i+1 < len(args) {
+				i++
+				tokenFlag = args[i]
+			}
+		default:
+			filtered = append(filtered, args[i])
+		}
+	}
+
+	switch subCmd {
+	case "schedule":
+		commands.RunCalendarSchedule(filtered, tokenFlag)
+	case "show":
+		commands.RunCalendarShow(filtered, tokenFlag)
+	case "edit":
+		commands.RunCalendarEdit(filtered, tokenFlag)
+	case "cancel":
+		commands.RunCalendarCancel(filtered, tokenFlag)
+	case "date-list":
+		commands.RunCalendarDateList(filtered, tokenFlag)
+	case "plan-schedule":
+		commands.RunCalendarPlanSchedule(filtered, tokenFlag)
+	case "plan-list":
+		commands.RunCalendarPlanList(filtered, tokenFlag)
+	case "plan-edit":
+		commands.RunCalendarPlanEdit(filtered, tokenFlag)
+	case "plan-cancel":
+		commands.RunCalendarPlanCancel(filtered, tokenFlag)
+	default:
+		output.Errorf("hf calendar %s is not implemented yet", subCmd)
+	}
+}
+
 func handleProposalCommand(subCmd string, args []string) {
 	tokenFlag := ""
 	var filtered []string