Split CLI command stubs into separate files

Move each command function from main.go into its own file
(deploy.go, lifecycle.go, status.go, etc.) to enable parallel
development by multiple workers without file conflicts.

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

cmd/mcp/node.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+func nodeCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "node",
+		Short: "Node management",
+	}
+
+	list := &cobra.Command{
+		Use:   "list",
+		Short: "List registered nodes",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return fmt.Errorf("not implemented")
+		},
+	}
+
+	add := &cobra.Command{
+		Use:   "add <name> <address>",
+		Short: "Register a node",
+		Args:  cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return fmt.Errorf("not implemented")
+		},
+	}
+
+	remove := &cobra.Command{
+		Use:   "remove <name>",
+		Short: "Deregister a node",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return fmt.Errorf("not implemented")
+		},
+	}
+
+	cmd.AddCommand(list, add, remove)
+	return cmd
+}