Add mcproxyctl CLI for gRPC admin API

Introduces a new command-line tool for managing mc-proxy via the gRPC
admin API over Unix socket. Commands include route and firewall rule
CRUD operations, health checks, and status queries.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/mcproxyctl/status.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/spf13/cobra"
+)
+
+func statusCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "status",
+		Short: "Show server status",
+		Long:  "Show server status including version, uptime, and listener information.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			client := clientFromContext(cmd.Context())
+
+			ctx, cancel := context.WithTimeout(cmd.Context(), 5*time.Second)
+			defer cancel()
+
+			status, err := client.GetStatus(ctx)
+			if err != nil {
+				return fmt.Errorf("getting status: %w", err)
+			}
+
+			fmt.Printf("mc-proxy %s\n", status.Version)
+			if !status.StartedAt.IsZero() {
+				uptime := time.Since(status.StartedAt).Truncate(time.Second)
+				fmt.Printf("uptime:      %s\n", uptime)
+			}
+			fmt.Printf("connections: %d\n", status.TotalConnections)
+			fmt.Println()
+
+			for _, ls := range status.Listeners {
+				fmt.Printf("  %s  routes=%d  active=%d\n", ls.Addr, ls.RouteCount, ls.ActiveConnections)
+			}
+
+			return nil
+		},
+	}
+}